[44] The ‘Report’ on M. Martin St. Ange’s memoir was laid before the Academy of Sciences, July 14, 1834, so that I suppose it was read previously to this date. R. Wagner’s paper was published in ‘Müller’s Archiv,’ 1834, p. 467. Burmeister’s ‘Beiträge zur Naturgeschichte der Rankenfüsser,’ was published this same year, 1834; so that these three authors published almost contemporaneously.
[45] A far better figure is given by Karsten (‘Nov. Act. Acad. Cæs. Nat. Cur.,’ 1845, Pl. 20, figs. 2, 3, 4), but under the erroneous supposition that these organs were hepatic.
[46] In Conchoderma aurita, the ducts, as shown by Burmeister (‘Beiträge,’ &c. tab. ii, fig. 17), unite half way up the probosciformed penis.
I have seen the spermatozoa in [Balanus crenatus], [perforatus], and [balanoides], and in [Chthamalus stellatus]. The cells, from which the spermatozoa are developed, and which are often found in vast numbers within the vesiculæ, are on an average about 1/5000th of an inch in diameter. The spermatozoa differ remarkably within the vesicula of the same individual, according to their state of development. I have observed in [B. perforatus] and in the [Chthamalus], that the shortest, and therefore, I presume, the youngest (Pl. [29], fig. [7], a), had a globular head with no projection in front: as they increased in size, this head became less in diameter, and a short tapering filament, (a, b,) like the tail, projected out of it. This anterior filament does not lie in exactly the same line with the posterior filament, which is straight as an arrow. In [Bal. crenatus], the anterior filament was 1/2000th of an inch in length, and the posterior filament 4/2000th, giving a total length of 5/2000th: in the longest and best developed specimens of [Chthamalus stellatus], the nodular enlargement was much elongated and spindle-shaped, and not above half the diameter it had in the earliest stage; the posterior filament (measured from the front of the enlargement, this consequently being included) was 5/2000th in length, and the front part only 1/4000th, giving a total length of 11/4000ths of an inch. These observations agree pretty well with Kölliker’s;[47] but this author states, that perfectly developed spermatozoa are absolutely without any nodular enlargement: if this be the case, I have never chanced to see the spermatozoa in their perfect condition. Mr. Bate, also, figures some (Pl. [29], fig. [7], c) in this state, without any enlargement.
[47] ‘Annales des Sciences Naturelles,’ (2d series), tom. xix, p. 348. Kölliker refers to Wagner’s paper on the same subject, in Wiegmann’s ‘Archiv,’ 1835, part ii, pl. iii, fig. 9. He also refers to Von Siebold’s observations. Mr. C. Spence Bate has figured, in the ‘Annals and Magazine of Natural History’ (vol. viii, 2d series, 1851), the spermatozoa of [Balanus balanoides], [perforatus], and of [Verruca (Clitia) Strömia], and of these I have given copies, Pl. [29], fig. [7].
The probosciformed penis lies adpressed on the under side of the thorax, with its apex generally projecting between the first and second pairs of cirri. It presents the same ringed or articulated structure as in the Lepadidæ: it arises from an unarticulated projection or support, which also forms the posterior border to the anus. This support often terminates, as first observed by Poli, in a very sharp point; but this point cannot be of much functional importance, for though present in [Balanus balanoides], it is absent in the closely allied [B. crenatus]; in [Tubicinella] there is only a rudiment of this point; I have not observed it in any member of the [Chthamalinæ]. The strong, transverse and longitudinal muscles with which the penis is furnished, are attached to this support. The apex or orifice of the penis is, I believe, invariably surrounded by some bristles. Its length varies much, according to its state of contraction or relaxation; and this again, I believe, is dependent on the condition of the male secreting organs. In a small specimen of [Elminius modestus], the penis was actually thrice as long as the whole thorax, including the prosoma: in [Pachylasma] and in [Octomeris angulosa], the penis is very short, being equal only to once and a half the length of the pedicel of the sixth cirrus: in [Octomeris brunnea], the unarticulated support is much elongated, being as long as the pedicel of the sixth cirrus, in which respect this organ resembles that of Ibla quadrivalvis, and of no other Cirripede. From the attachment of the penis at the posterior end and on the under side of the anus—from the position of the caudal appendages (where such occur) over the anus—from the position of these same appendages in the pupa—and lastly, from the position of the papilla-like penis in the abnormal [Proteolepas], I infer that, homologically, the penis is situated at the apex of the abdomen, on its ventral surface; and that, consequently, this organ cannot be considered as the abdomen itself in a modified condition.
Female Organs of Generation.
I have scarcely anything to add to the statements in my former volume. These organs consist of the true ovaria, or glandular bodies seated on each side, not far from the basal edge of the labrum; of the main or unbranched ovarian ducts; and of the (Pl. [25], fig. [1], g) ovarian branching tubes and cæca. I traced distinctly in [Balanus], [Tetraclita], and [Coronula], the two main ovarian ducts, running from within the prosoma to the layer of inosculating, branching, ovarian cæca[48] which overlie the basis. In [Coronula diadema] one of these main ducts was 1/100th of an inch in diameter. Though I traced these ducts near to the grape-like, glandular masses,[49] which I cannot doubt are the true ovaria, I did not succeed in tracing them into actual connection. As in the Lepadidæ, these ovarian glands lie on the sides, near the basal margin of the labrum, and almost under, but rather to the outside of the antennular nerves. The branching and inosculating ovarian cæca form a layer, which corresponds with the mass filling up the peduncle in the Lepadidæ. In [Tetraclita] they do not cover the whole basis, but are confined to the circumference; they, however, likewise extend up between the two layers of corium round the walls of the shell, and chiefly in the interspaces between the depressor muscles of the opercular valves. In [Chelonobia], they enter between the radiating septa in the thickness of the walls: in [Coronula diadema], they extend from over the basal membrane into the six large square chambers (Pl. [16], fig. [7], v) separating the radii and alæ: in [Tubicinella] they are confined to the basis: in [Xenobalanus], they form a layer over the basis and likewise round the upper part of the peduncle-like body, which answers to the shell of other sessile cirripedes.
[48] These are well described in Lepas, by R. Wagner, in ‘Müller’s Archiv,’ 1834, p. 467. Von Siebold, I observe, refers to Burmeister as the first author who discovered the ovarian cæca within the peduncle; I had thought that M. Martin St. Ange had a prior claim.
[49] These are obscurely figured by Karsten (‘Nov. Act. Acad. Cæs. Nat. Cur.,’ 1845, Pl. 20, fig. 1d) as salivary glands; they were so considered by Cuvier and M. Martin St. Ange: I may observe that salivary glands have not been positively recognised in any Crustacean.