DESCRIPTION OF FRAGMENTS OF BONES, AND OF OSSEOUS TESSELATED DERMAL COVERING OF LARGE EDENTATA.

It is now determined that there once existed in South America, besides the Megatherium, the Megalonyx, and the allied genera described in the preceding pages of the present work, gigantic species of the order Bruta belonging to the Armadillo family, and defended, like the small existing representatives of that family, by a tesselated bony dermal covering. The largest known species of these extinct Dasypodidæ is the Glyptodon clavipes, of which the armour and parts of the skeleton have been described by MM. Weiss and D’Alton in the Berlin Transactions for 1827 and 1834: and the generic and specific characters and name, with an account of the dental system, and bones of the extremities, were recorded in the Geological Proceedings for March 1839. It would seem that parts of the same, or a nearly allied gigantic species were described in the same year by M. Lund; under the name of Hoplophorus. Of the valuable and interesting discoveries of this able Naturalist I regret that I was not aware until the appearance of a notice of them in the Comptes Rendus for April, 1839.[[64]] Amongst the fragments of bony tesselated armour in Mr. Darwin’s collection are a few pieces which were found by him, associated with remains of Toxodon and Glossotherium near the Rio Negro in Banda Oriental.[[65]] These fragments, if we may judge from their thickness, must have belonged to an animal at least as large as the Glyptodon clavipes; but the pattern differs in the greater equality of size of the component tesseræ. The thickness of the largest fragment is one inch and a half, the tesseræ vary in diameter from one inch to half an inch, and are separated by grooves about two lines in depth, and two in diameter. The pattern formed by the anastomosis of these grooves is an irregular net-work; the contour of the tesseræ is either unevenly subcircular, hexagonal, pentagonal, or even four-sided; with the sides more or less unequal. In those portions of this armour, where one of the tesseræ exceeds the contiguous ones in size, the imagination may readily conceive it to be the centre of a rosette, around which the smaller ones arrange themselves, but there is no regular system of rosettes, as in the portions of the dermal armour of the Glyptodon figured by Weiss, and those brought to England by Sir Woodbine Parish, in which the central piece is double the size of the marginal ones.

The portions of the tesselated bony dermal covering of a Dasypodoid quadruped, figured in Pl. [XXXII]. figs. 5 and 4, of the natural size, were discovered folded round the middle and ungueal phalanges, figs. 2 and 3, at Punta Alta, in Bahia Blanca, in an earthy bed interstratified with the conglomerate containing the remains of the fossil Edentals.

In one of these fragments, measuring six inches long by five broad, the tesseræ are arranged in rosettes, and so closely correspond in size and pattern with the bony armour described by M. Lund, as characterizing his species, Hoplophorus euphractus, that I feel no hesitation in referring them to that animal. One of the pattern rosettes is figured at fig. 4, together with the thickness of the armour at this part, and the coarse tubulo-cellular structure of the bone. Another portion of dermal armour from the same locality, gives the pattern shown in fig. 5, formed by square or pentagonal tesseræ, arranged in transverse rows; it is certain that this portion of armour belonged to the same animal as the preceding piece; and probably that it constituted part of the transverse dorsal bands of the Hoplophorus.

The middle and ungueal phalanx, as well as the portions of armour, are given of the natural size, in Pl. [XXXII]. The upper and outer surface of the phalanx, is shown in fig. 2. It is smooth and flat; joins the inner surface by a sharp edge, which runs along the upper and inner side of the bone; and passes by a gradual convexity to the under surface; the ridge corresponding with the base of the claw, is feebly developed at the under and lateral parts of the base of the claw. Below the double trochlear joint for the middle phalanx, there are two articular surfaces for two large sesamoid bones.

The middle phalanx corresponds in its small antero-posterior diameter and wedge-shape, with that of the great Glyptodon: but the terminal phalanx is longer and deeper, in proportion to its breadth.

Among the collection of fossils from Punta Alta, in Bahia Blanca, there is an interesting fragment of the head of a gigantic animal of the Edentate order, including the glenoid cavity, and part of the zygomatic process of the left side. The articular surface for the lower jaw, exhibits, in its flatness, extent, and the absence of a posterior ridge, the well-marked characteristics of this part of the Edental structure. It measures two inches four lines in the transverse, and two inches two lines in the antero-posterior diameter. The commencement of the zygomatic process presents a vertical diameter of two inches, and a transverse diameter of eight lines at the thickest part. It is slightly concave at its lower border, and convex above. The small portion of the cranial parietes, which is preserved, exhibits the cellular structure consequent upon the great extension and development of the nasal air-sinuses: this condition of the cranial parietes, has already been noticed in the description of the more perfect skulls of the large extinct Edentata.

NOTICE OF FRAGMENTS OF MOLAR TEETH OF A
MASTODON.

Of the remains of this gigantic extinct Pachyderm, observed by Mr. Darwin at Santa Fé, in Entre Rios, and on the banks of the Tercero, the fragments of the teeth and portions of the skeleton which reached England, are not sufficient to lead to a determination of the species; but sufficiently prove it to have been nearly allied, if not identical, with the Mastodon angustidens of Cuvier, and unquestionably distinct from the Mastodon giganteum of the United States.

NOTICE OF THE REMAINS OF A SPECIES OF
EQUUS,

Found associated with the extinct Edentals and Toxodon at Punta Alta, in Bahia Blanca, and with the Mastodon and Toxodon at Santa Fé, in Entre Rios.

The first of these remains is a superior molar tooth of the right side; it was embedded in the quartz shingle, formed of pebbles strongly cemented together with calcareous matter, which adhered as closely to the tooth in question, as the corresponding matrix did to the associated fossil remains. The tooth was as completely fossilized as the remains of the Mylodon, Megatherium, and Scelidothere; and was so far decomposed, that in the attempt to detach the adherent matrix, it became partially resolved into its component curved lamellæ. Every point of comparison that could be established proved it to differ from the tooth of the common Equus Caballus only in a slight inferiority of size.

The second evidence of the co-existence of the horse with the extinct Mammals of the tertiary epoch of South America reposes on a more perfect tooth, likewise of the upper jaw, from the red argillaceous earth of the Pampas at Bajada de Santa Fé, in the Province of Entre Rios.[[66]]

This tooth is figured at Pl. [XXXII]. fig. 13 and 14, from which the anatomist can judge of its close correspondence with a middle molar of the left side of the upper jaw.

This tooth agreed so closely in colour and condition with the remains of the Mastodon and Toxodon, from the same locality, that I have no doubt respecting the contemporaneous existence of the individual horse, of which it once formed part.

This evidence of the former existence of a genus, which, as regards South America, had become extinct, and has a second time been introduced into that Continent, is not one of the least interesting fruits of Mr. Darwin’s palæontological discoveries.

DESCRIPTION OF REMAINS OF RODENTIA, INCLUDING THE JAWS AND TEETH OF AN EXTINCT SPECIES OF
CTENOMYS.

The fragment of the upper jaw, figured in Pl. [XXXII]. fig. 6, exhibits the first and second molar in situ, and the socket of the third and fourth molar, of a Rodent, which by the form and number of the upper maxillary teeth is referable to the genus Ctenomys. The molars are a little larger, the longitudinal groove on their external surface is somewhat deeper, and the last molar is relatively wider than in the existing subterraneous species,—the Tucutucu (Ctenomys Brasiliensis, Bl.), of whose habits so interesting an account is given in the description of the Mammalia of the present Collection (No. IV. p. 79). The form of the grinding surface of the first and second upper molar is shown below the fig. 6, and three views of the second grinder are given at figs. 7, 8, and 9. The fragment of the lower jaw of the same fossil Rodent is figured at fig. 10 and 11. The long anterior incisor is relatively narrower than in the Ctenomys Brasiliensis. I have not had the means of comparing this fossil with the Ctenomys Magellanicus; but since it is probable that the Ct. Magellanicus may not be specifically different from the Ct. Brasiliensis, it may be concluded that the present fossil is equally distinct from both.

The portion of the right hind-foot of the Rodent figured at fig. 12, includes the calcaneum, astragalus, cuboides, external and middle cuneiform bones, and the metatarsals and proximal phalanges of the toes corresponding with the three middle toes of five-toed quadrupeds. The metatarsals are chiefly remarkable for the well-developed double-trochlear articular surface, and intermediate ridge. These remains, as well as the jaws and teeth of the Ctenomys, were discovered at Monte Hermoso in Bahia Blanca.

In the same reddish earthy stratum of that locality, Mr. Darwin discovered the decomposed molar of a Rodent, equalling in size, and closely resembling in the disposition of its oblique component laminæ, the hinder molar of the Capybara (Hydrochærus). The fossil differs, however, in the greater relative breadth of the component laminæ.

I have, lastly, to notice the head of a femur, and some fragments of pelvic bones from the same formation which bear the same proportion to the tooth above alluded to, as subsists between the teeth and bones of the Capybara, and which are sufficient to prove that there once has existed in South America a species of the family Caviidæ, as large as the present Capybara, but now apparently extinct.

This fact, together with the greater part of those which have been recorded in the foregoing pages of the present work, establishes the correspondence, in regard to the characteristic type, which exists between the present and extinct animals of the South American Continent: we have abundant evidence likewise of the greater number of generic and specific modifications of these fundamental types which the animals of a former epoch exhibited, and also of the vastly superior size which some of the species attained.

At the same time it has been shewn that some of the present laws of the geographical distribution of animals would not have been applicable to South America, at the period when the Megatherioids, Toxodon, and Macrauchenia existed: since the Horse, and according to M. Lund, the Antelope and the Hyæna, were then associated with those more strictly South American forms. The Horse, which, as regards the American continent, had once become extinct, has again been introduced, and now ranges in countless troops over the pampas and savannahs of the new world. If the small Opossums of South America had been in like manner imported into Europe, and were now established like the Squirrels and Dormice in the forests of France, an analogous case would exist to that of the Horse in South America, as the fossil Didelphys of Montmartre proves.

With respect to the geological contemporaneity of the fossils collected by him, Mr. Darwin subjoins the following observations:—

“The remains of the following animals were embedded together at Punta Alta in Bahia Blanca:—The Megatherium Cuvierii, Megalonyx Jeffersonii, Mylodon Darwinii, Scelidotherium leptocephalum, Toxodon Platensis (?) a Horse and a small Dasypodoid quadruped, mentioned p. 107; at St. Fé in Entre Rios, a Horse, a Mastodon, Toxodon Platensis, and some large animal with a tesselated osseous dermal covering; on the banks of the Tercero the Mastodon, Toxodon, and, according to the Jesuit Falkner, some animal with the same kind of covering; near the Rio Negro in Banda Oriental, the Toxodon Platensis, Glossotherium, and some animal with the same kind of covering. To these two latter animals the Glyptodon clavipes, described by Mr. Owen in the Geological Transactions, may, from the locality where it was discovered, and from the similarity of the deposit which covers the greater part of Banda Oriental, almost certainly be added, as having been contemporaneous. From nearly the same reasons, it is probable that the Rodents found at Monte Hermoso in Bahia Blanca, co-existed with the several gigantic mammifers from Punta Alta. I have, also, shown in the Introduction, that the Macrauchenia Patachonica, must have been coeval, or nearly so, with the last mentioned animals. Although we have no evidence of the geological age of the deposits in some of the localities just specified, yet from the presence of the same fossil mammifers in others, of the age of which we have fair means of judging, (in relation to the usual standard of comparison, of the amount of change in the specific forms of the invertebrate inhabitants of the sea,) we may safely infer that most of the animals described in this volume, and likewise the Glyptodon, were strictly contemporaneous, and that all lived at about the same very recent period in the earth’s history. Moreover, as some of the fossil animals, discovered in such extraordinary numbers by M. Lund in the caves of Brazil, are identical or closely related with some of those, which lately lived together in La Plata and Patagonia, a certain degree of light is thus thrown on the antiquity of the ancient Fauna of Brazil, which otherwise would have been left involved in complete darkness.”

LONDON:

PRINTED BY STEWART AND MURRAY,

OLD BAILEY.

Pl. I.
G. Scharf del et lithog. Printed by C. Hallmandel.
Base of the Skull of Taxodon Platensis.
Nat. Size.
Published by Smith, Elder & Cº͈ 65, Cornhill, London.

Pl. II.
G. Scharf del et lithog. Printed by C. Hallmandel.
Side View of the Skull of Taxodon.
One-third the Natural Size.
Published by Smith, Elder & Cº͈ 65, Cornhill, London.

Pl. III.
G. Scharf del et lithog. Printed by C. Hallmandel.
Top View of the Skull of the Taxodon.
One-third the Nat. Size.
Published by Smith, Elder & Cº͈ 65, Cornhill, London.

Pl. IV.
G. Scharf del et lithog. Printed by C. Hallmandel.
Taxodon Platensis.
Published by Smith, Elder & Cº͈ 65, Cornhill, London.

Pl. V.
G. Scharf del et lithog. Printed by C. Hallmandel.
Fragments of the lower Jaw and Teeth of a Taxodon.
Nat. Size.
Published by Smith, Elder & Cº͈ 65, Cornhill, London.

Pl. VI.
G. Scharf del et lithog. Printed by C. Hallmandel.
Cervical Vertebræ of Macrauchenia.
Published by Smith, Elder & Cº͈ 65, Cornhill, London.

Pl. VII.
G. Scharf del et lithog. Printed by C. Hallmandel.
Cervical Vertebræ of
1, 2. Macrauchenia 3,4 Auchenia.
Published by Smith, Elder & Cº͈ 65, Cornhill, London.

Pl. VIII.
G. Scharf del et lithog.
Lumbar Vertebræ, Macrauchenia.
Fig. 1. Posterior View of last lumbar. Fig: 2,3&4. Fourth lumbar Vertebra.
Nat. Size.
Published by Smith, Elder & Cº͈ 65, Cornhill, London.

Pl. IX.
Lithog. from Nature by G. Scharf.
Macrauchenia.
Fig. 1_2. Scapula. Fig. 3. Femur.
Published by Smith, Elder & Cº͈ 65, Cornhill.

Pl. X.
G. Scharf del et lithog.
Proximal Extremity of anchylosed Ulna and Radius Macrauchenia.
⅔ Nat. Size.
London, Published by Smith, Elder & Cº͈ 65, Cornhill.

Pl. XI.
G. Scharf del et lithog. Printed by C. Hallmandel.
Bones of the right fore-foot, Macrauchenia.
Fig. 1, ⅔, 2_9, Nat. Size.
Published by Smith, Elder & Cº͈ 65, Cornhill.

Pl. XII.
Lithog. from Nature by G. Scharf. Printed by C. Hallmandel.
⅔ Nat. Size.
Right Femur. Macrauchenia.
Published by Smith, Elder & Cº͈ 65, Cornhill.

Pl. XIII.
Lithog. from Nature by G. Scharf. Printed by C. Hallmandel.
Macrauchenia.
Right Tibia and Fibula.—Fig. 2_4. ⅔ Nat. Size.
Published by Smith, Elder & Cº͈ 65, Cornhill.

Pl. XIV.
Lithog. from Nature by G. Scharf.
Right Astragalus., Macrauchenia.
Nat. Size.
Published by Smith, Elder & Cº͈ 65, Cornhill.

Pl. XV
Lithog. from Nature by G. Scharf. Printed by C. Hallmandel.
Macrauchenia.
Fig. 1. Metatarsal. 2_5. Metacarpals. Nat. Size.
Published by Smith, Elder & Cº͈ 65, Cornhill.

Pl. XVI.
Lithog. from Nature by G. Scharf. Printed by C. Hallmandel.
Fragment of the Cranium of the Glossotherium
½ Nat. Size.

Pl. XVII.
Fig. 3. 4. Laurillard del. Fig. 5. G. Scharf del et lithog. Printed by C. Hallmandel.
1. Megalonyx Jeffersoni. 2. Meg. laqueatus. 3. 4. Mylodon Harlani. 5. Myl. Darwinii.
Published by Smith, Elder & Cº͈ 65, Cornhill.

Pl. XVIII
G. Scharf del et lithog. Printed by C. Hallmandel.
Mylodon. ⁵⁄₉ Nat Size.

Pl. XIX
G. Scharf del et lithog. Printed by C. Hallmandel.
Mylodon.
Fig 1. ⁵⁄₉ Nat. Size. Fig. 2.3.4. Nat. Size.

Pl. XX.
Lithog. from Nature by G. Scharf. Printed by C. Hallmandel.
Scelidotherium.
⅔ Nat. Size.
Published by Smith, Elder & Cº͈ 65, Cornhill.

Pl. XXI.
G. Scharf del et lithog. Printed by C. Hallmandel.
Scelidotherium.
Fig 1 & 2 ⅔ Nat. Size. Fig 3_5. Nat. Size.
Published by Smith, Elder & Cº͈ 65, Cornhill, London.

Pl. XXII.
Lithog. from Nature by G. Scharf. Printed by C. Hallmandel.
Scelidotherium.
Published by Smith, Elder & Cº͈ 65, Cornhill, London.

Pl. XXIII.
Lithog. from Nature by G. Scharf.
Cranial Cavity and Dentition of Scelidotherium.
Nat. Size.
Published by Smith, Elder & Cº͈ 65, Cornhill.

Pl. XXIV.
Lithog. from Nature by G. Scharf.
Cervical and Anterior dorsal Vertebræ
Fig: 1. Scelidothere. Fig: 2. Orycterope. Fig: 3. Armadillo. Fig:4. Great Ant-eater.
One-third Nat. Size.
Published by Smith, Elder & Cº͈ 65, Cornhill.

Pl. XXV.
Lithog. from Nature by G. Scharf. Printed by C. Hallmandel.
Scelidotherium ⅓ Nat. Size.
Published by Smith, Elder & Cº͈ 65, Cornhill.

Pl. XXVI.
Printed by C. Hallmandel.
Left Astragalus
Fig. 1.3.5. Megatherium: ⅓ Nat. Size. 2.4.6 Scelidotherium. ⅔ Nat. Size.
Published by Smith, Elder & Cº͈ 65, Cornhill.

Pl. XXVII.
Lithog. from Nature by G. Scharf.
Scelidotherium.
Fig. 1.2. ⅔ Nat. Size. 3.4.5 Nat. Size.
Published by Smith, Elder & Cº͈ 65, Cornhill.

Pl. XXVIII.
Lithog. from Nature by G. Scharf. Printed by C. Hallmandel.
Left Astragalus.
Fig. 1. Megatherium. ⅓ Nat. Size. Fig: 2. Scelidotherium. ⅔ Nat. Size. Fig. 3–6, Mylodon.? ⅔ Nat. Size.

Pl. XXIX.
Lithog. from Nature by G. Scharf. Printed by C. Hallmandel.
Lower Jaw of Megalonyx.
Fig. 1. ⅔. Fig. 2. Nat. Size.

Pl. XXX.
Lithog. from Nature by G. Scharf. Printed by C. Hallmandel.
Megatherium ½ Nat. Size

Pl. XXXI.
Lithog. from Nature by G. Scharf. Printed by C. Hallmandel.
Section of the superior maxillary teeth,
Megatherium.
¾ Nat. Size.

Pl. XXXII.
Lithog. from Nature by G. Scharf. Printed by C. Hallmandel.
1. Megatherium. 2_5. Hoplophorus. 6_12. Ctenomys. 13_14. Equus.

[1]. See Ossemens Fossiles, Ed. iv. tom. ii. p. 368. Pl. 27. fig 1. 12.

[2]. Ibid. p. 370. Pl. 27. fig. 5.

[3]. Ibid. p. 347, 367.

[4]. Ibid. p. 337. Pl. 26. fig. 7.

[5]. Philosophical Transactions, vol. lviii. p. 34. (1768.)

[6]. Bridgewater Treatise, p. 139.

[7]. Geological Transactions, vol. iii. p. 437. pl. 44, 45, 46.

[8]. Quoted by Cuvier, Ossem. Foss. Ed. iv. tom. ii. p. 351.

[9]. Τοξον, arcus; οδους, dens.

[10]. Mem. de l’Acad. des Sciences de Paris, 1764, p. 568.

[11]. True fangs exist only in teeth of temporary growth, they may be one or more in number, but always diminish in size as they recede from the crown of the tooth, and are either solid, or with a very small canal.

[12]. This was written before an examination of the fragment of a lower jaw, forming part of Mr. Darwin’s collection of Fossil Remains, had led me to suspect that it was referrible to the genus Toxodon; should this suspicion prove correct, the four unequal incisors of the upper jaw are opposed to six equal sized ones in the lower.

[13]. I have ascertained that this elastic ligament exists in the neck of the Dugong.

[14]. The German Translator (See Frorieps Notizen., 1837, p. 119) of the abstract of my description of the Toxodon, published in the Proceedings of the Geological Society, asks, what is the Mutica (misprinted Muticata), of Linnæus? The term is quoted from the Systema Naturæ, Ed. xii. p. 24. Linnæus first divides Mammalia into three groups, according to modifications of the locomotive organs, viz. Unguiculata, Ungulata, Mutica, and subdivides these, according to modifications of the dentary organs, into the orders, Bruat, Glires, Primates, &c.

[15]. Besides the relation to food requiring much comminution, which teeth with persistent pulps bear, they are also connected with the longevity of the individual. The term of life in a herbivorous animal, with grinders of temporary growth, is, of necessity, dependent on the duration of these essential aids to nutrition; thus, a sheep generally wears down its grinders in twelve years, and its natural term of life is consequently limited to about that period.

[16]. Μακρος longus, αυχην cervix: from the latter word Illiger derived Auchenia, his generic name of the Llama, Vicugna, &c.

[17]. In the seventh cervical vertebra of the Camel, as in many other Mammalia, there is no perforation in any part for the vertebral arteries. In a Vicugna, I find the same structure; but in a Llama, the side of the body of the seventh cervical vertebra is perforated longitudinally on the right side. In the Camel, the vertebral arteries pierce the sixth cervical vertebra, immediately below the superior transverse processes, and pass obliquely to the anterior aperture of the cervical canal, where they emerge beneath the anterior oblique processes, and then enter the spinal canal of the fifth cervical vertebra, as described in the text.

[18]. Cuvier, Ossemens Fossiles, iii. p. 238.

[19]. Loc. cit. p. 234.

[20]. Loc. cit. p. 235.

[21]. Loc. cit. p. 237.

[22]. Loc. cit. p. 232.

[23]. See Ossem. Fossiles, Pl. [XX]. fig. 3.

[24]. Loc. cit. Pl. [XXII]. fig. 6.

[25]. See Ossem. Foss. iii. Pl. [XXVI]. fig. 5.

[26]. This diameter increases rapidly in the posterior lumbar vertebræ, in correspondence with the enlargement of the spinal chord, which gives off the great nerves of the hinder extremities.

[27]. The relative breadth of these bones is shown in the figures of the fore-foot, Pl. [XI].

[28]. The figures in Pl. [XIV]. preclude the necessity of giving the admeasurements of the astragalus.

[29]. “Comme le genre de vie de chaque animal est toujours en rapport avec les mouvements dont sa mâchoire est susceptible, on retrouve dans la conformation des surfaces destinées à l’articulation, les particularités qui semblent le déterminer d’avance. Ainsi dans les animaux qui vivent de chairs, substances filamenteuses qui ne peuvent être écrasées, mais seulement coupées et dechirées, le mouvement de la mâchoire inférieure ne peut s’exécuter que de haut en bas. Dans les herbivores, les frugivores et les granivores, comme le principal mouvement est celui de broiement pour écraser, comprimer les herbes et les fruits, pour briser les grains et les réduire, en pâte, le mouvement des mâchoires se fait encore de droite à gauche, et réciproquement, on en même temps, de devant en arrière, en un mot, dans un plan horizontal autant que dans un vertical: les uns représentent des ciseaux, les autres des meules de moulin.”

[30]. In the monotrematous Echidna, the large canal for the lingual nerve has a widely different direction and course from that in the placental Edentata.

[31]. Transactions of the Philosophical Society of Philadelphia, vol. iv. p. 246.

[32]. Its relations to the Edentata, previously conjectured by Dr. Wistar, are proved in the Annales du Muséum, tom. v. p. 358; its more immediate affinities as an annectant form in that group are discussed in the edition of the Ossem. Fossiles, of 1833, tom. v. pt. 1. p. 160.

[33]. Speaking of this tooth, Cuvier observes, “Je l’avois cru d’abord nécessairement de paresseux; mais aujourdhui que je connois mieux l’ostéologie des divers tatous, je trouve qu’elle ressemble au moins autant à une dent de l’un des grands tatous.”—Loc. cit. p. 172.

[34]. Synopsis Mammalium.

[35]. It is most probable that the substance which is here termed “enamel,” is similar to that which forms the dense prominent ridges in the tooth of the Megatherium, and which I have shown to be composed of minute parallel calcigerous tubes, similar to the ivory or bone of the human tooth.

[36]. Medical and Physical Researches, pp. 323–4.

[37]. Loc cit. p. 330.

[38]. Spix and Martius, Reise in Brazil, Band ii. p. 5.

[39]. Harlan’s Medical and Physical Researches, 1835, p. 334. M. de Blainville speaks of a cast of a fragment of a lower jaw “portant encore cinq dents en série;” as having been transmitted to the Museum of the Garden of Plants from North America, together with other bones, all of which he refers to the genus Megalonyx; M. de Blainville does not describe these teeth, which is to be regretted, inasmuch as, if he be correct in regard to their number, which can hardly be doubted, and if he wrote with any clear and definite ideas of the generic characters of Megalonyx, this would indicate that Megalonyx differed generically both from Megatherium and Mylodon in a more important dental character than has hitherto been suspected (See “Comptes Rendus, &c.” 1839, No. V. p. 142.)

[40]. Dr. Harlan also indicates differences in certain parts of the skeleton of the New York fossils as compared with his Megx. laqueatus; but thinks them probably due to a difference in the age of the individuals: he says “There is also in Mr. Graves’ collection, in New York, a tibia, nearly perfect from the right leg; the segment of a flattened sphere, on which the external condyle of the femur moves, is rather more depressed, than in the specimen from Big-bone-cave. Other marks and peculiarities are observable on this bone, not found on that of the Megalonyx laqueatus of Big-bone-cave, but they are probably due to a difference in the age of the individuals.” Loc. cit. p. 335.

[41]. Μυλη, mola; οδους, dens.

[42]. If the lower jaw of Mylodon Harlani, bears the same proportion to its teeth as does that of Mylodon Darwinii, it must be about two feet in length.

[43]. See Proceedings of the Geological Society, March 1839, and Parish’s Buenos Ayres, p. 178, b, Pl. 1, fig. 2 and 3.

[44]. Σκελις, femur; Θηριον, bellua; in allusion to the disproportionate size of the thigh-bone.

[45]. This beach is covered at spring tides; many parts of the skeleton were encrusted with recent Flustræ, and small marine shells were lodged in the crevices between the bones.

[46]. It requires little stretch of imagination to conceive that this more complex posterior tooth (Pl. [XXIII]., fig. 4, 4) in the lower jaw is the representative of the two smaller posterior teeth (ib. fig. 3, 4, and 5) of the upper jaw conjoined.

[47]. Lund, Videnskabernes Selskabs, Natur.: og Mathem. Afhandlinger, Kiöbenhavn, vol. viii.

[48]. Linn. Trans. vol. xvii. (1833) p. 17.

[49]. Zool. Proceedings, 1832, p. 134.

[50]. The anterior prolongation of the sternum in front of the neck and the corresponding anterior position of the clavicles and scapulæ occasions a transference of such a proportion of the moving powers of the head from the cervical vertebræ to these bones in the mole, as renders any modifications of these vertebræ, like those in the Armadillo, uncalled for.

[51]. Loc. cit.

[52]. Bridgewater Treatise, p. 46.

[53]. Bridgewater Treatise, p. 152.

[54]. Dasypus 6–cinctus, L., is the species of which I have the astragalus separate, so as to be able to follow out the comparison.

[55]. In distinguishing these trochleæ as fibular and tibial, it is to be understood that the terms relate only to aspects corresponding to the position of those bones, and not that the fibula is articulated to the whole of the trochlea so called: it probably rested only upon the outer facet in the Scelidothere.

[56]. This astragalus was found at Santa Fé, in Entre Rios, associated with the remains of the Mastodon and Toxodon; but from its size and form I entertain little doubt that it belonged to a Megatherioid quadruped as large as the Mylodon or Megalonyx. The brief allusion to the astragalus of the Megalonyx in M. Lund’s Memoir does not afford the means of determining with certainty this point.

[57]. See the figures of this bone, given by Cuvier in Pl. x. and xi. Ossemens Fossiles, vol. v. part i.

[58]. Ossemens Fossiles, vol. v. part i. p. 163.

[59]. For the translation of the following passage, and of others alluded to in the present work, from the original Danish Memoir of M. Lund, loc. cit., I am much indebted to the Rev. W. Bilton, M.A. &c. &c.:—

“Thus in every point of comparison we have instituted between the organization of burrowers and climbers; we have seen that the Megalonyx constantly differs from the former and resembles the latter; but the point to which I last alluded (the obliquity of foot), I consider to be quite decisive.

“There is one other point in its organization, which is not quite without weight in reference to our present inquiry,—I mean its unusually powerful tail. Now, it is certainly true that many animals which are not climbers have a powerful tail, as e. g. Armadillos, while the others that climb well, have none, as Sloths and Apes. But when we find a remarkably powerful tail attached to an animal that according to all probability was a climber, we are led to infer that this organ must have served for that purpose: in other words, that the Megalonyx was furnished with a prehensile tail.

“How far the Megatherium is to be considered in the same light as the Megalonyx cannot be decided without an accurate and scientific examination of its skeleton at Madrid. Pander and D’Alton do not mention any distortion of the hind-foot, neither does their figure exhibit any. It is nevertheless quite possible that such may exist, but that it is disguised by the faulty manner in which the skeleton is put up. It strikes me as little probable that two animals which agree so well in the principal particulars of their organization should differ so much in one of the most important. The Megatherium has been proved by later discoveries to possess the same powerful tail as the Megalonyx, and as it corresponds also with the latter entirely in the conformation of its extremities, the same difficulties present themselves against the supposition of its having been a burrower. But if the Megatherium was really a climber, it must have had still more occasion (on account of its greater size), for that peculiar arrangement of the hind-feet which we have described in the Megalonyx.”

[60]. Descripcion del Esqueleto de un quadrupedo muy corpulento y raro, que se conserva en el Real Gabinete de Historia Natural de Madrid. Folio, Madrid, 1796.

[61]. Ossemens Fossiles, tom. v. pt. i. p. 179.

[62]. “Das Riesen Faulthier, Bradypus giganteus, von Dr. Chr. Pander und Dr. E. D’Alton.” Folio, Bonn, 1821.

[63]. Transactions of the Geological Society, 1835, p. 438.

[64]. An excellent translation of the description of the Brazilian fossils found by M. Lund, is published in the Annals of Natural History, July and August, 1839.

[65]. At the distance of a few leagues from the locality here mentioned, other fragments were found by Mr. Darwin; also near Santa Fé, in Entre Rios; also on the shores of the Laguna, near the Guardia del Monte, South of Buenos Ayres; also, according to the Jesuit Falkner, on the banks of the Tercero.

[66]. Mr. Darwin has more particularly described the circumstances of the embedment of this tooth in his Journal of Researches, p. 149, during the Voyage of the Beagle.

TRANSCRIBER’S NOTES

  1. The [Errata] was corrected.
  2. Silently corrected obvious typographical errors and variations in spelling.
  3. Retained archaic, non-standard, and uncertain spellings as printed.
  4. Re-indexed footnotes using numbers and collected together at the end of the last chapter.