The Opisthohyancliiata of South Africa. 33 



broad, the two long efferent ducts in their last, about 2 mm. long, 

 portion gray, as were also their pear-formed ampulla. The gl, 

 ptyalina and its duct as in the typical species. 



The cesophagus violet-black. The liver grayish yellow, 9 mm. long 

 by a breadth of 7. 



The praebranchial sack (fig. 7) rather bent, extended nearly 6 mm. 

 in length. 



The hermaphrodite gland whitish, about 5 mm. broad by a thick- 

 ness of 2. The anterior genital mass whitish, 5 mm. long by a 

 height and breadth of 3 ; the prostata of a diameter of 2 5 mm. ; 

 the coils of the continuation of the vas deferens extended 3 cm. in 

 length, much longer than represented by Vayssiere (I.e., p. 49 ; 

 pi. 4, fig. 232cfZ), but absolutely different from the relations of the 

 organ in PI. Meckelii-'' ; the internal sheath of the vas deferens 

 projecting (fig. 8) 1'2 mm. (0*05 mm. broad) from the end of 

 the penis. 



The forms here examined differ from the typical one by the 

 absence of the caudal finger and the very different relations of 

 the vas deferens. It may be that it is really the PI. capensls of 

 Vayssiere ; the individuals which have been examined by Vayssiere 

 as well as by me, have been too insufficient to settle the question 

 with certainty. 



2. Pleurobranch^a melanopus, B. n. sp, 

 PI. IV., figs. 12-15. 



Off Cape Point (NE. by E. 36 miles) one individual was caught 

 by shrimp-trawl from a depth of 650 fms. ; the bottom was green 

 mud. 



The length was 2-4 by a breadth of 1-5, and a height of 1-3 cm. ; 

 the height of the rhinophores 4, of the tentacles 3 mm. ; the length 

 of the gill 5 mm. by a breadth of 2-5 ; the breadth of the foot 

 8 mm., the length of the caudal gland 3 mm. by a breadth of 1. — 

 The animal very likely had been velvet-black all over, but on the 

 back this colour only remained on the head and partly towards the 

 margin ; elsewhere it seemed rubbed off ; the dirty yellowish colour 

 of the gill, with traces of black on the rhachides, of the cleft prte- 

 branchial organ, and of the outer genitals as well as of the caudal 

 gland, contrasted with the black of their surroundings. 



The anterior margin of the tentacular veil with 2-3 series of small 

 nodules. The back quite even. The gill somewhat flattened, with 



* Cf. my MoDogr. of the Pleurobranchidae (I.e., v. 1897, p. 25-26; taf. iii., 

 fig. 22; taf. iv., figs. 36, 4c, 56. 



3 



