THE CAKNIVOKOUS SLUGS OF SOUTH AFRICA. 205 



21, 24). — Animal sometimes slightly swollen towards the 

 middle, tapering to a blunt point at the hind end. Back 

 rounded, without keels. Outer lip of respiratory opening- 

 narrow, exposing the inner lip. Skin covered with a 

 network of grooves, among which the main grooves are less 

 conspicuous than in the other species of Apera. Dorsal 

 grooves about 1 mm. apart (notwithstanding the small size of 

 the species), usually separated by a double row of rugte, 

 but united for about 3 mm. in front of the respiratory 

 opening. Lateral grooves rather near the dorsal grooves, 

 irregular, but sometimes extending as far as the head. 

 Oblique sub-lateral grooves also irregular, seldom reaching 

 the peripodial groove, and less numerous than in A. 

 gibbo n si, being usually absent from the anterior third of 

 the animal. Radial grooves fairly well marked dorsally, but 

 like the sub-lateral grooves they cannot always be traced as 

 far as the peripodial groove. The upper limits of the lowest 

 rug^e on each side often form an irregular longitudinal groove 

 near the peripodial groove and parallel to it. 



Body conspicuously mottled with greyish-brown pigment, 

 which is chiefly concentrated to form an irregular and some- 

 what discontinuous dark band along each side of the animal. 

 Between these bands is a much paler dorsal area only 

 sparsely mottled, darkest around the anterior border of the 

 respiratory opening and lightest at the edges next to the 

 dark bands. Below these the skin is darker than it is 

 dorsally, being more thickly mottled, especially next to the 

 dark band, though the pigmentation extends down to the 

 peripodial groove. Both dorsally and laterally there is a 

 tendency for some of the pigment to be concentrated in the 

 dermal grooves, thus emphasizing the reticulation. Small 

 patches of the same pigment are sparsely scattered over the 

 foot-sole. The ground-colour of specimens preserved in 

 spirit is yellowish white. 



The following are the dimensions (in alcohol) of two 

 specimens, in both of wdiich the reproductive organs were 

 fully developed : 



