50 Marine Investigations in South Africa. Vol. V. 



prostata of a diameter of 4 mm., the globulous sperm atotheca 

 of 2 mm. diameter. 



This form seemed to be a Diaulula and very hkely a new species. 



2. Diaulula ? morosa, B. n. sp. 

 PL v., figs. 23-26. 



One specimen of this form was found on the shore at Mossel Bay. 



It had a length of 14 by a breadth of 6 and a height of 3 mm., tlie 

 height of the rhinophores 1-5, the diameter of the gill-aperture 2-5, 

 and the height of the branchial leaves 1"5 ; the breadth of the foot 

 3'25 mm. — The back of this animal was of a uniform dark greenish 

 gray colour, the foot white. 



The form was elongate-oval, rounded behind and in front with 

 somewhat prominent brim of the villous back ; the lamellae of the 

 rhinophores not thin ; the gill consisting of 10 simply pinnate 

 leaves, protruding from the roundish gill-opening ; the tentacles 

 small; the foot shorter than the back, with prominent brim. 



The back densely covered with rather low villi of a height up to 

 0"2 mm., stiffened with spicules in and often around them (fig. 23) ; 

 the skin of the back containing masses of dark pigment and many 

 spicules. 



The bulhus pharyngeus 2 mm. long, whitish ; the lip disc with a 

 strong, much folded, colourless cuticle (no armature). The rasp of 

 the tongue nearly colourless, with many rows of plates and many 

 plates in the series ; the plates colourless, reaching a height mostly 

 of 0'016 mm., of the common hook form (fig. 24), the outermost (6) 

 very thin and slender, with short basal plate, reaching a height of 

 0-14 mm. (figs. 25, 26). 



The liver longish, 6 mm. long, clear grayish yellow. 



The anterior genital mass whitish. The penis short, peai'-shaped ; 

 the glans short, conical, with yellowish cuticle. 



The generic position of this animal is quite uncertain ; in many 

 respects it would seem to belong to the Diaululidae, but the leaves of 

 the gill are simply pinnate. 



THOEDISA, Bgh. 

 E. Bergh, System, I.e., 1892, p. 1098. — Die Opisthobranchiata d. 

 Siboga Exped., 1905, pp. 121-124. 



Thordisa punctulifera, B. n. sp. 

 PI. VI., figs. 1-4. 

 In False Bay (Kockland Point bearing NW. \, N. 2h miles) three 

 specimens were taken by large dredge, together with a species of 



