The Tail Muscles
The muscles of the tail have, as shown by Gadow, the character of the primitive body muscles, with their primitive metameric division, fairly plainly preserved. This musculature is arranged in four rows of trumpet-shaped cones, one projecting into the other, by which arrangement each metamere exhibits a transverse zigzag line of four anteriorly and three posteriorly directed points.
Ilio-ischio-caudalis ([Plate III.], Figs. 1 and 2, is. cd., [Plate IV.], Figs. 1 and 2, is. cd.) (Ischio-coccygeus). The crocodile is the nearest to the typical condition in the musculature of the tail. The lateral and ventral part of the tail musculature forms a broad mass that extends to the end of the tail; it lies immediately under the skin and springs from the caudal ribs (transverse processes—Gadow) and from the spinous processes of all the caudal vertebræ. The entire side musculature of the tail ends cephalad in several portions; the most ventral and medial of these bound the cloaca as an at least slightly developed, morphological sphincter; the lateral portion is attached to the posteroventral border of the ischium; while the dorsal portion is inserted by two heads on the first caudal rib and on the posterior spine of the ilium.
Plate I.
Shoulder Muscles of Crocodilus Acutus. (From Bronn after Fürbringer.)
Fig. 1. Shoulder Muscles after Removal of the Sphincter Colli Muscle (sphr).
Fig. 2. Shoulder Muscles after Removal of the Sphincter Colli Muscle (sphc).
Fig. 3. Deep Layer of the Inner Shoulder Muscles after Removal of the Humerus and its Musculature as well as the Collo-Scapularis Superficialis Muscles (cssp) and Thoraci-Scapularis Superficialis Muscles (thcsp).
Fig. 4. Shoulder Muscles after Removal of the Pars Scapularis of the Supra-Coraco-Scapularis (sps) and of the Biceps Muscle (b).
Fig. 5. Different View of Fig. 4.
Fig. 6. Shoulder Muscles after Removal of the Pars Coracoidea of the Supra-Coraco-Scapularis (spc) and Deltoides Scapularis Superior (dss) Muscles.
Lettering for All Figures of this Plate.
acs, ahl, ahp, asl, coraco-scapular, humerale laterale, humerale posticum, and scapulare laterale externum heads of the anconæus muscle; b, coraco-antebrachialis (biceps); c, coracoid; cbb, coraco-brachialis; cc, costo-coracoideus; Cl, clavicle; cssp, collo-scapularis superficialis (levator scapulæ superficialis); cst, capiti-sternalis (sterno-mastoideus); cthspr, collo-thoraci-scapularis profundus (levator scapulæ and serratus profundus); cu, dorso-scapularis (cucullaris); dh, dorso-humeralis (latissimus dorsi); dsi, deltoides scapularis inferior; dss, dorsalis scapulæ (deltoides scapularis superior); Ec, epicoracoid; Est, episternum; esthy, episterno-hyoideus; H, humerus; hai, humero-antebrachialis inferior (brachialis inferior); hr, humero-radialis; p, pectoralis; PL, processus lateralis humeri; PM, processus medialis humeri; R, radius; rh, rhomboideus; S, scapula; sbsc, subscapularis; shpr, scapulo-humeralis profundus; spc, supra-coraco-scapularis; sphc, sphincter colli; SpS, spina scapulæ; SS, suprascapulare; St, sternum; Sta, anterior part of sternum; Stp, posterior part of sternum; thssp, thoraci-scapularis superficialis (serratus superficialis); U, ulna; V₅, V₆, 5th and 6th vertebræ.
Nerves Shown in this Plate.
| 3a. | thoracicus VII. |
| 7. | posterior branch of the thoracicus superior VII for the collo-thoraci-suprascapularis profundus and rhomboideus muscles. |
| 7a. | proximal. |
| 7b. | distal thoracicus superior VII. |
| 10a. | thoracicus inferior. |
| 12. | supra-coracoideus. |
| 15. | integumental, (13 and 14), muscular branch of the supra-coracoideus. |
| 19. | pectoralis. |
| 21. | brachialis longus inferior. |
| 29b. | teres major. |
| 31. | dorsalis scapulæ (posterior). |
| 32. | cutaneus brachii and antebrachii superior lateralis. |
| 32a. | humero-radialis. |
| 33. | deltoides inferior, (25 and 42), cutaneus brachii and antebrachii medialis. |
Plate II.
Figs. 1-4. Muscles of the Forearm of the Alligator.
(From Bronn.)
Figs. 5-7. (From Bronn after Rathke.)
| Fig. 1. | 1, humero-radialis longus (supinator longus); 2, humero-radialis medialis(flexor carpi radialis); 3, carpo-phalangei I digiti V; 4, carpo-phalangei(flexor digitorum communis brevis); 5, humero-ulno-phalangei (flexordigitorum communis profundus); 6, humero-radialis longus; s. flexor carpiulnaris; 7, pisiforme-phalangeus primus digiti V; 8, carpo-phalangeus I;9, carpo-metacarpalis I. |
| Fig. 2. | 1-5 as in Fig. 1; a, humero-carpi-radialis; b, humero-metacarpalis III,IV, V (extensor digitorum longus); c, humero-carpi-ulnaris; d, carpo-phalangei(extensor-digitorum brevis). |
| Fig. 3. | a, b, humero-ulno-phalangei (flexor digitorum communis profundus). |
| Fig. 4. | a, ulno-carpi-radialis; b, ulna; c, humero-ulnaris-lateralis (flexor carpiulnaris); d, humero-radialis brevis (supinator brevis). |
| Fig. 5.Head, Neck, and a Part of the Body of a CrocodilusVulgaris. (Ventral View). | |
| a, lower jaw; b, upper jaw; c, arch of palate; d, fold of palate; h,pterygoideus internus (Rathke); i, pterygoideus externus (Rathke);k, longus colli (Rathke); m, rectus capitis anticus major (Rathke);n, sterno-mastoideus (Rathke); o, levator scapulæ (Rathke); p, scalenus(Rathke). | |
| Fig. 6. Part of a Similar Preparation of C. Rhombifer. | |
| a, the hindermost of the superior maxillary teeth; b, lower jaw; c,wings of palate; d, pterygoid; e, quadrate; g, intertransversalis (Rathke);h, trachelomastoideus (Rathke); i, levator scapulæ (Rathke); k, longuscolli (Rathke); m, pterygoideus externus (Rathke); n, rectus capitisanticus major (Rathke). | |
| Fig. 7. A Part of the Head and Neck of Alligator Lucius. | |
| a, pterygoideus externus (Rathke); b, digastricus (Rathke); c, rectuscapitis anticus major (Rathke); d, sterno-mastoideus, anterior belly(Rathke); e, sterno-mastoideus, posterior belly (Rathke); f, levatorscapulæ (Rathke); g, cervicalis adscendens (Rathke); h, longus colli(Rathke); i, intertransversalis (Rathke); k, trachelomastoideus (Rathke);l, biventer cervicis (Rathke); m, splenius colli (Rathke); n, spleniuscapitis (Rathke). | |
Plate III.
Fig. 1. Muscles of the Posterior Extremity of Alligator Mississippiensis. Left Side, Ventral (Plantar) Surface.
Fig. 2. The Same, Dorsal and Lateral Surfaces.
Fig. 3. A. Mississippiensis; the Tendons of the Flexor Tibialis Muscle in their Relation to the Gastrocnemius Muscle. Right Leg, Inner Surface. (Figs. 1-3 from Bronn, after Gadow.)
amb, ambiens; cap, ext, gastr, external head of gastrocnemius; cap, int, gastr, internal head of gastrocnemius; cd, fm, caudali-femoralis; cd, il, fem, caudi-ilio-femoralis; ex. il. tb. extensor ilio-tibialis; ext, l (long), dig, extensor longus digitorum; fl, tb, ext, flexor tibialis externus; fl, tb, int, flexor tibialis internus; fm, tb, femoro-tibialis; il, cd, ilio-caudalis; il, cost, ilio-costalis; il, fib, ilio-fibularis; il, fm (il, f), ilio-femoralis; il, s, cd, ilio-sacro-caudalis; is, cd, ischio-caudalis; is, f, ischio-femoralis; ob, ext, obliquus externus; pb, cd, pubi-caudalis; pb, is, tb, pubi-ischio-tibialis; pb, tb, pubi-tibialis; peron, ant, peroneus anterior; peron, post, peroneus posterior; p, is, f, ext, pubi-ischio-femoralis externus; p, is, f, int, pubi-ischio-femoralis internus; p, is, f, post, pubi-ischio-femoralis posterior; qudr, lb, quadratus lumborum; rect, rectus abdominis; tib, ant, tibialis anticus; tib, post, tibialis posticus; trans, transversus abdominis; tr, per, transversus perinei; m, post, il, posterior border of ilium; ob, foramen in pubis for the obturator nerve; o, il, ilium; o, is, ischium; o, pb, pubis; o, cl, cloacal bone; pr, l, pb, lateral process of pubis; pr, tr, transverse process; sp, ant, il, anterior spine of ilium; Sy, p, symphysis pubis; Sy, is, symphysis of ischium; tb, is, tubercle of ischium.
Plate IV. (From Bronn, after Gadow.)
Fig. 1. Alligator Mississippiensis. Inner Surface of the Pelvic Region, Left Side. The Pubis, Ischium, and Vertebræ are Cut through the Median Plane, XXVIII, 28th Vertebra.
Fig. 2. Hatteria Punctata.
Fig. 3. A. Mississippiensis. The Deepest Muscles on the Plantar Surface of the Left Hind Foot. Roman Numerals IX-XII, Short Toe Muscles.
Fig. 4. A. Mississippiensis. Left Leg from the Postero-mesial Aspect. The Plantar Flexor Musculature in Situ, after Removal of the Gastrocnemius Muscle and the Associated Muscles. Roman Numerals, VI-X, Short Toe Muscles.
amb, ambiens; cap, ext, gastr, external head of gastrocnemius; cap, int, gastr, internal head of gastrocnemius; cd, fm, caudali-femoralis; cd, il, fem, caudi-ilio-femoralis; ex, il, tb, extensor ilio-tibialis; ext, l (long), dig, extensor longus digitorum; fl, tb, ext, flexor tibialis externus; fl, tb, int, flexor tibialis internus; fm, tb, femoro-tibialis; il, cd, ilio-caudalis; il, cost, ilio-costalis; il, fib, ilio-fibularis; il, fm (il, f), ilio-femoralis; il, s, cd, ilio-sacro-caudalis; is, cd, ischio-caudalis; is, f, ischio-femoralis; ob, ext, obliquus externus; pb, cd, pubi-caudalis; pb, is, tb, pubi-ischio-tibialis; pb, tb, pubi-tibialis; peron, ant, peroneus anterior; peron, post, peroneus posterior; p, is, f, ext, pubi-ischio-femoralis externus; p, is, f, int, pubi-ischio-femoralis internus; p, is, f, post, pubi-ischio-femoralis posterior; qudr, lb, quadratus lumborum; rect, rectus abdominis; tib, ant, tibialis anticus; tib, post, tibialis posticus; trans, transversus abdominis; tr, per, transversus perinei; m, post, il, posterior border of ilium; ob, foramen in pubis for the obturator nerve; o, il, ilium; o, is, ischium; o, pb, pubis; o, cl, cloacal bone; pr, l, pb, lateral process of pubis; pr, tr, transverse process; sp, ant, il, anterior spine of ilium; Sy, p, symphysis pubis; Sy, is, symphysis of ischium; tb, is, tubercle of ischium.
Plate V. (From Bronn, after Gadow.)
Fig. 1. Hatteria Punctata. (Ventral View.)
Fig. 2. Alligator Mississippiensis. Left Posterior Extremity; Foot in Pronation, hence Seen from the Dorsal Side. lg, t, f, Ligamentum Tibio-Fibulare.
Fig. 3. A. Mississippiensis. Muscles of the Dorsal Surface of the Lower Leg and Foot.
amb, ambiens; cap, ext, gastr, external head of gastrocnemius; cap, int, gastr, internal head of gastrocnemius; cd, fm, caudali-femoralis; cd, il, fem, caudi-ilio-femoralis; ex, il, tb, extensor ilio-tibialis; ext, l (long), dig, extensor longus digitorum; fl, tb, ext, flexor tibialis externus; fl, tb, int, flexor tibialis internus; fm, tb, femoro-tibialis; il, cd, ilio-caudalis; il, cost, ilio-costalis; il, fib, ilio-fibularis; il, fm (il, f), ilio-femoralis; il, s, cd, ilio-sacro-caudalis; is, cd, ischio-caudalis; is, f, ischio-femoralis; ob, ext, obliquus externus; pb, cd, pubi-caudalis; pb, is, tb, pubi-ischio-tibialis; pb, tb, pubi-tibialis; peron, ant, peroneus anterior; peron, post, peroneus posterior; p, is, f, ext, pubi-ischio-femoralis externus; p, is, f, int, pubi-ischio-femoralis internus; p, is, f, post, pubi-ischio-femoralis posterior; qudr, lb, quadratus lumborum; rect, rectus abdominis; tib, ant, tibialis anticus; tib, post, tibialis posticus; trans, transversus abdominis; tr, per, transversus perinei; m, post, il, posterior border of ilium; ob, foramen in pubis for the obturator nerve; o, il, ilium; o, is, ischium; o, pb, pubis; o, cl, cloacal bone; pr, l, pb, lateral process of pubis; pr, tr, transverse process; sp, ant, il, anterior spine of ilium; Sy, p, symphysis pubis; Sy, is, symphysis of ischium; tb, is, tubercle of ischium.
