PSEUDAUSTENIA. 207 



lying open to the apex, and a slightly raised division alone sepa- 

 rating the apical whorl. 



Animal with shell-lobes turned over the shell and coalescing 

 round it, not covering it when preserved in spirit. Right shell- 

 lobe extending back towards apex, then terminating in a rounded 

 end. Left shell-lobe continuous with right anteriorly, but separate 

 behind. The left dorsal or neck-lobe covers a considerable part 

 of the neck and extends along the left side to behind the shell. 

 Back of foot behind the mantle flattened, not keeled, divided an- 

 teriorly into two well-developed lappets, forming between them a 

 deep V-shaped depression, in which the shell and mantle are sunk. 

 The posterior end of the foot terminates in a small linear mucous 

 pore, overhung by a small lobe, the peripodial groove well marked ; . 

 sole of foot tripartite longitudinally. 



After removing the shell the uppermost of the visceral sac 

 whorls are seen to be more developed in the animal than is usual 

 in slug-like forms, the small hooked process of the liver-lobes 

 [filling the apex of the shell] being much better developed than in 

 Girasia. In the genitalia there is no dart-sac, the speroiatheca is 

 a globular sac on a tube ; the male organ is simple, bent on itself at 

 the retractor muscle, on the proximal side of which it is consider- 

 ably expanded to form the spermatophore (fig. 72) just beyond 

 the junction of the vas deferens, but there is no kale-sac or 

 flagellum, nor is there any caecum leading to the retractor 

 muscle. 



[Radula 24 . 1 . 19 . 1 . 19 . 1 . 24 (44 . 1 . 44)]. The broader 

 teeth in the middle elongate and tricuspid ; the outer teeth small 

 and bicuspid, only one cusp terminal. 



This is distinguished from the African genus Africarion by its 

 very different shell, its back lappets, and by the form of the 

 male organ, which in Africarion [is much more simple, the vas 

 deferens joining the shaft of the penis at the retractor muscle, 

 there being no epiphalhis. It differs materially from Austenia 

 and Girasia in the shell, the absence of the amatorial organ, and 

 the general form of the male organ, which has a penis papilla. 

 Neither has it any relationship to Ibycus nor Parmacochlea as put 

 forward by Mr. T. D. A. Cockerell (P. Z. S. 1891), the first genus 

 being shown by its radula to belong to the Durgellince. The 

 internal anatomy of Parmacochlea is in many points most unlike 

 that of Pseudaustenia atra.~] 



312. Pseudaustenia atra, Godwin-Austen (Africarion), Mol. Ind. 

 i, 1888, p. 244, pi. 57, figs. 1-6 (animal, anatomy, and shells) ; 

 vars. aterrima, cinerea, and castanea, /. c. p. 245. 



Shell ovate, slightly convex above, concave below, smooth, 

 covered with a straw-coloured or green rnembranaceous epidermis, 

 which overlaps the peristome to a considerable extent ; whorls 1|, 

 the apex, as in Austenia, is flat. All the lower surface of the shell 



