90 NILS HJ. ODHNER, MOLLUSCA. 
FAM. RATHOUSIIDAE. 
? Atopos (Prisma) australis HEYNEMANN (PI. 3, figs. 99—100; text figs. 45—51). 
Herberton (Jan. 1913), 1 sp., I. 45 mm. — As no good description or figure has 
been published either of this species or the closely allied ÅA. prismatica TAPPARONE 
CANEFRI (1883), I am not sure which of these species the present specimen repre- 
sents. It is different from both in the dark, blackish gray, foot sole, but whether 
this is a specific or individual characteristic it is impossible to say without examining 
Fig. 45. Atopos australis(?) HEYNEMANN. Position Fig. 46. Anatomy of Atopos australis(?). t. foot 
of the openings: a. cloaca (anus and urethra pore); gland; g. hermaphrodite gland; gl. albuminiparous 
8. pulmonary orifice; 9 female genital opening. gland ; l. liver; m. muscles; n. central ganglia; p- 
d. penis gland ; p. m. retractor penis; per. pericard; 
r. rectum; s. d. »spin gland»; r. s. radula sac; st. 
stomach ; u. nephridium; v. 8. receptaculum semi- 
nis; w. »white glands». The white broken line 
marks the extension of the stomach lumen. 
more comprehensive material. I therefore prefer to range it under the previously 
known Australian (Queensland) species and to give a good figure and a detailed 
description for future identification. 
The present specimen had the anterior end strongly retracted beneath its notum, 
so that neither tentacles nor mouth were visible. The exterior characteristics agree 
with the descriptions that SIMROTH (1891) has put together from the literature on 
the allied forms. In its outline the body has a narrowly elliptic shape with tapering 
ends; the dorsal side is very elevated and forms a sharp keel which gives the body 
an equilaterally triangular section with somewhat convex sides (cf. fig. a of SIMROTH 
1891). The sides of the notum are densely set with larger and smaller, regularly 
