2 Transactions of the South African Philosophical Society. 



between the fauna of the West side of the Cape of Good Hope 

 Peninsula and that of the East. The latter has more of a tropical 

 Indian character, the former a somewhat more Northern, although 

 typically tropical forms of Nudibranchiata {e.g., the Melibe) are not 

 wanting. 



TECTIBRANCHIATA. 



ANASPIDEA. 



APLYSIIDiE. 



Aplysiid^e propria. 



I. Aplysia, L. 



Linne, Syst. Nat., ed. xii., 1767, p. 1072. 

 Cuvier, Tableau Elem. (1798) an v., p. 386, pi. ix., fig. 3. 

 Lamarck, Syst. des Anim. s.v. 1801, p. 62. 



E. Eergh, Die Opisthobranchiata der Siboga Expedition, 1905, 

 p. 3. 



1. Apl. Gilchristi, B. n. sp. 



Animal colore brunneo albo-maculato. 



PL I., figs. 1-3 ; PL X., fig. 1. 



A living specimen was procured in Ealse Bay in February, 1905 

 •(PL X., fig. 1). It was brown in colour, the sides of the foot with 

 many small white spots and white border, the outer border of the 

 wings with larger white blotches, and many fine black perpendicular 

 lines on their outer side. It swam dexterously and at a fair speed 

 through the water. 



The animal, in a contracted condition (preserved in formalin), had 

 a length of 6'5 cm. and, with raised parapodia, a height of 3 and a 

 breadth of 2*5 ; the breadth of the head (with its 7 mm. long tenta- 

 cles) 2 cm., the height of the rhinophores 6 mm., the length of the 

 mantle-shield 2*5 cm., its breadth 2, the length of the sipho 1, the 

 breadth of the foot proper (sole) 9 mm., the length of the tail 8, 

 the length of the foot-wings 4 cm., with an inside height of 1*7. — 

 The colour of the sole of the foot is blackish brown with a whitish 

 margin, the animal otherwise of a dark brown colour, whitish rather 

 elongate spots on the sides of the body, some also on the outside of 

 the wings and a series of larger blots along the margin, the inside of 

 the wings of the same brown colour with a few whitish spots towards 



