218 



MISS RUTH C. BAMBER ON 



The urinary system was not connected in any way with the 

 genital system, the right and left ureters joining together to 

 form a short common canal which opened separately into the 

 cloaca, on a papilla behind the female genital opening. 



There does not appear to be any other record of hermaphro- 

 ditism in Scyllium ; but Semper*, in 1875, recorded a rudimentary 

 testis in a female Hexanchus. 



The specimen which is described below came from Port Erin, 

 Isle of Man. It was unfortunately so badly damaged that the 

 description is necessarily incomplete. 



Externally the animal was a typical male ; the claspers were 

 well developed, and the pelvic fins were united together along 

 almost the whole length of their inner edges. 



Internally, both male and female organs were present. Both 

 testes were developed, and except for the lobate character of the 

 left testis, looked normal when seen from the ventral surface 

 (PI. I. fig. 1). On the dorsal surface, however, the right testis 

 showed a small mass of ova developed at the anterior end, on 

 the inner side. Dissection showed that the ovarian part formed 

 about half the thickness of the right gonad, and was confined to 

 the anterior end (PI. II. fig. 4). The oviducts were normal, and 

 each had an oviducal gland. The right duct and gland were con- 

 siderably larger than the left. The ducts opened together into 

 the ccelom anteriorly as in a normal female. Posteriorly they 

 were united together by their adjacent walls for about 2 cm., 

 but their cavities remained distinct (PI. I. fig. 2). The external 

 opening was not seen. 



The male ducts were well developed. The vasa efierentia 

 were not seen because of the damage to the mesentery, but on 

 each side there was a well-defined epididymis, and a long, narrow, 

 convoluted vas deferens, increasing in diameter posteriorly to form 

 the straight vesicula seminalis. Sperm-sacs were not present 

 (fig. 2). Posteriorly each vesicula seminalis united with the dorsal 

 wall of the oviduct of its own side, and for a short distance 

 after uniting, the right one ran parallel with the oviduct and 

 then opened into it. The left one, however, ran obliquely in the 

 wall of the left oviduct towards the median line of the body until 

 it reached the wall separating the two oviducts, and then opened 

 into the right one, side by side with the opening of the right 

 vesicula seminalis (PI. II. fig. 3). No papilla was formed, but 

 a little fold of the wall of the oviduct surrounded the two male 

 genital openings, so that they lay in a slight depression. 



The interrelationship of the genital ducts, as also the complete 

 development of the oviducts coupled with the absence of sperm- 

 sacs, might suggest the possibility that the sperm-sacs are 

 normally developed from the posterior ends of the degenerate 

 oviducts. The specimen described by Yayssiere and Quintaret, 



* Semper, " Das Urosenitalsystem der Plagiostonien und seine Bedeutung fur das 

 der iitrigen Wirbelthiere," Arb. last. -Wmzburg, 13d. 2, 1875, pp. 195-509 (see 

 p. 278 & Taf. xiv.). 



