208 HUGH WATSON. 



External Characters (PL VIII, fig. 25; and 'Ann. S. Afr. 

 Mus./ vol.ii, pi. xiv, figs. 1,2). — Animal rather broad anteriorly, 

 tapering to a blunt point at the hind end. Back rounded, with- 

 out keels. Outer lip of respiratory opening narrow, exposing 

 the inner lip. Skin with well-marked reticulation, the rugas 

 being rather large for the size of the slug. Dorsal grooves 

 less than 4- mm. apart, separated throughout their length by 

 a single row of rugee, not united in front of the respira- 

 tory opening. Radial grooves well-developed, and extending 

 down to the single peripodial groove, which is not very deep. 

 The most anterior radial grooves branch from the dorsal 

 grooves near the respiratoiy opening, instead of arising from 

 the opening itself. There is not even a trace of lateral 

 grooves, excepting perhaps for a very short distance ; but 

 irregular oblique grooves occur in front of the radial grooves, 

 and these correspond to the sub-lateral grooves of other 

 species. 



Body dark grey or bluish black, the pigment being chiefly 

 concentrated in the dermal grooves and thus emphasizing the 

 reticulation. On each side there is a suggestion of a slightly 

 darker lateral band, the intervening dorsal area being a little 

 paler, although it tends to be darker towards the centre than 

 next to the obscure lateral bands. Below these the skin 

 becomes much lighter, the pigment dying out completely 

 before it reaches the peripodial groove. The foot and the 

 ground-colour of the back is whitish yellow in the case of 

 specimens preserved in spirit, but in living examples the foot 

 is said to be ferruginous. 



According to Mr. Collinge the type (in alcohol) is 2.5 mm. 

 long, and its foot-sole is 4 mm. in breadth. I have only seen 

 a young specimen, of which the following are the measure- 

 ments : 



Length . . .16 mm. Greatest height . 3"5 mm. 



Breadth in middle •3'75 „ Distance from resp. 



Breadth at resp. opening to hind 



opening . . 2*25 „ end . . . 3"75 „ 



Breadth of foot-sole 2 ,, 



