[335] Chapter VI. p. [345], et seq.
[336] Archiv f. Micr. Anat. Bd. XI.
[337] “Urogenital System d. Plagiostomen,” Semper, Arbeiten, Vol. II.
[338] Sitzungsberichte d. Naturfor. Ges. Leipzig, 1875. No. 2.
[339] “Preliminary account of the development of Elasmobranch Fishes,” Quarterly Journal of Microscopical Science, 1874. “Origin and History of the Urinogenital Organs of Vertebrates,” Journal of Anat. and Physiol. Vol. X.
[340] Arbeiten, Semper, Vol. III.
[341] Though Professor Semper has come to the same conclusion as myself with respect to these homologies, yet he calls the Wolffian body Leydig's gland after its distinguished discoverer, and its duct Leydig's duct.
[342] The term segment will be more accurately defined below.
[343] My observations on this subject completely disprove, if it is necessary to do so after Professor Semper's investigations, the statement of Dr Meyer, that segmental tubes in Scyllium open into lymph organs.
[344] I feel considerable hesitation in accepting Semper's descriptions of the ureters and their openings. It has been shewn above that for Scyllium his statements are probably inaccurate, and in other instances, e.g. Raja, I cannot bring my dissections to harmonise with his descriptions.