The Opisthobranchiata of South Africa. 39 



were scattered over the head and the upper side of the brim of the 

 foot; the upper lip of the marginal furrow of the anterior end of 

 the foot brownish. — The length was 3 cm. by a breadth (of the back) 

 of 2 and a height of 1-3 ; the frontal veil 14 mm. broad, the breadth 

 ■of the mantle-brim 5 ; the length of the gill 16 mm. by a breadth of 

 5 and a height of 4 ; the breadth of the foot 22 mm., that of the 

 brim 4. 



The form as usual. The number of the lamellae in the gill about 

 25, the vesicles along the rhachis very distinct ; the external genital 

 organs nearly without prominent folds ; the caudal gland, very 

 indistinct, seemed 7 mm. long. 



The nature of the shell could not be determined. 



The nervous system as usual. The skin contained a quantity of 

 cells and groups of not calcified cells. 



The mouth tube 3 mm. long. The bulbus pharyngeus (with the 

 prominent rasp-sheath) 9 mm. long by a breadth of 7 and a height 

 of 4. The mandibles clear reddish yellow, 7 mm. long by a height of 

 3*5, in a length of 2*5 mm. denudated. Their elements brownish 

 yellow, 0-26 mm. long by a breadth of 014 and a height of 04 ; 

 behind the pointed hook on each side 4 denticles, of which the upper 

 the largest (fig. 22). The rasp of the tongue of a clear yellow colour, 

 the number of series of plates was large, and so too the number in 

 the rows. The plates with yellowish basal part, otherwise nearly 

 colourless ; the height of the 4 innermost (fig. 23) 0*035-O04-0'06- 

 and - 08 mm., quickly mounting to O20, then gradually to 025, then 

 decreasing; the height of the three outermost (fig. 26) was 0-035- 

 0-06-0-10 mm. The inner half of the series, or thereabout, had the 

 hook of the plates somewhat crooked (fig. 24) ; in the remainder it 

 was straighter (fig. 25). 



The gland, ptyalina not much developed. The liver brownish gray, 

 contrasting in colour to the yellowish white hermaphrodite gland. 



This form is distinctly different from the Oscaniella granulata 

 described by me (I.e., pp. 113-115, tab. ix., figs. 17-22) as being the 

 Pleurobranchus granulatus of Krauss, which seems to be a Berthella. 



It is possible that it represents a variety of Osc. nigropunctata. 



BERTHELLA, Blv. 



Berthella, Blainville. Man. de Malacol., 1825, pp. 469, 627, 



pi. xliii., fig. 1. 

 Cleanthus, Leach. Moll. Brit, syn., 1852, p. 28. 

 Berthella, Blv. R. Bergh, Die Opisthobr. d. Siboga Exp., 1905, 



pp. 68-73. 



