Amblystomidæ.
Salamandridæ.
III. Gymnophiona.
[43] I am under great obligations to Mr Parker for having kindly supplied me, in answer to my questions, with a large amount of valuable information on the development of the Amphibia.
[44] Within the vitelline membrane there appears to be present, in the Anura at any rate, a very delicate membrane closely applied to the yolk.
[45] Allen Thomson informs me that he has watched the process of fertilization in the Newt, and that the male deposits the semen in the water close to the female. From the water it seems to enter the female generative aperture. Von Siebold has shewn that there is present in female Newts and Salamanders a spermatic bursa. In this bursa the spermatozoa long (three months) retain their vitality in some Salamanders. Various peculiarities in the gestation are to be explained by this fact.
[46] For a summary of these and the literature of the subject vide “Amphibia,” by C. K. Hoffmann, in Bronn’s Classen und Ordnungen d. Thier-reichs.
[47] Vide Spengel, “Die Fortpflanzung des Rhinoderma Darwinii.” Zeit. f. wiss. Zool., Bd. XXIX., 1877. This paper contains a translation of a note by Jiminez de la Espada on the development of the species.
[48] Since the body cavity is not developed as diverticula from the cavity of invagination, the latter cavity may conveniently be called the mesenteron and not the archenteron.
[49] Vide Huxley, “Craniofacial apparatus of Petromyzon.” Journ. of Anat. and Phys. Vol. X. 1876. Huxley’s views about the Meckelian arch, etc., are plausible, but it seems probable from Scott’s observations that true branchial bars are not developed in the Lamprey. How far this fact necessarily disproves Huxley’s views is still doubtful.