100 
Rissoia (Amphithalamus) Simsoni, spec. nov. 
Pupiform, strong, shining, white, tinted with pale-chestnut.. 
Whorls four, flatly convex, sculptured with microscopie oblique: 
strie; suture linear. Apex hemispheric of one and a-half 
whorls. Last whorl somewhat flattened on the ventral face. 
Aperture oval; peristome continuous, adnate to the parietal 
wall. Resem les R. dissimilis on a large scale. 
Length, 4:5 ; width, 1:5 m 
Species-name in compliment to our friend and co-worker, Mr. 
Auguste Simson of Launceston. 
Derwent — Tasmania ( W. L. May); also Port Fairy, 
Victoria (Rev. 7. Whan /). 
Rissoia (Cingula) rubicunda, spec. nov. 
Shell minute, elevated conic, imperforate, nn thick ; 
varies in colour from pellucid-brown to opaque-w 
ul obtuse, of one and a-half turns. Spire. EDER four, 
moderately convex, widest near the anterior suture 
examples show a tendency to imbrication), smooth, and sculptured 
with growth-lines. Suture linear, distinct. Last whorl rather 
depressed at the suture, rounded at the periphery, a little con- 
tracted at the outer lip. 
Aperture rotund, chestnut-coloured in the interior ; peristome 
entire ; outer lip thin ; columella lip slightly exsert, margining a 
false umbilical chink. 
Length, 2:5; width, 1:0 
Derwent Estuary, a (W. L. May); many examples. 
This may prove to belong to Buen when the animal has. 
been studied. 
perexigua, nom mutand. 
Rissoia ER Ten.-Woods, P.R.S. rcge DU p. 122 
non Rissoia minutissima, Michelin, ** Gen. Risso 
Rissoia (Nodulus) pellucida, spec. nov. 
Shell minute, obliquely oad somew ven stout, translucent-white,. 
P 
smooth, shining, imper us small, obtuse. Spire- 
whorls three and a-half, pisei resur slantingly convex, 
without visible ornament or sculpture. Aperture roundly oval ;. 
peristome thick, continuous. 
B. "15 mm 
Frederick Henry Bay, Tasmania (W. L. May). 
s species ditfers from other members of the section by its. 
Littorina-like shape; however, the following species in Section 
ina offer some comparisons vimm has the outline of 
R. hyalina, which possesses spiral raised strie and delicate 
growth-lines, and it is more obliquely oval than A. littorineformis. 
