author's abstract of this paper issued 



BY the bibliographic SERVICE, MARCH 28 



THE COMPARATIVE MORPHOLOGY OF THE 

 SECONDARY SEXUAL CHARACTERS 

 OF ELASMOBRANCH FISHES 



THE CLASPERS, CLASPER SIPHONS, AND CLASPER GLANDS 

 • MEMOIR II 



W. HAROLD LEIGH-SHARPE 



FIFTEEN TEXT FIGURES 



The preceding memoir, which appeared in the Journal of Mor- 

 phology, volume 34, page 245, contained a general introduction 

 to the subject, a list of references, and a consideration of Scyl- 

 lium catulus, Scyllium canicula, Acanthias vulgaris, and Raia 

 circularis. In it the following nomenclature was adopted. The 

 term siphon was given to a muscular sac ending blindly anteriorly, 

 and opening posteriorly near the proximal end of the clasper. 

 Its cavity is the siphon sac. In Raia, and as will presently be 

 seen in Lamna also, the sac is almost filled by a gland — the 

 clasper gland. The apopyle was defined as the proximal or 

 anterior entrance to the clasper groove, or tube, and the hypopyle 

 as the distal, or posterior exit therefrom. The parasiphons are, 

 in Scyllium, a pair of similar and similarly situated sacs to the 

 siphons, though much smaller and probably vestigial in func- 

 tion. The siphons and parasiphons debouch by a common 

 exedra. 



The rhipidion is a fan-like expansion near the distal extremity 

 of the clasper, posterior to the hypopyle, attaining a greater 

 development in Raia and Galeus, whose function is partly to 

 spread the ejected spermatozoa in a radiating manner and partly 

 for attachment during copulation. To these terms some new 

 ones, such as pseudosiphons and perae, will now be added and 

 defined in their proper places. 



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