160 LITTORINIDA. 
Judging from this single specimen, a very distinct small 
form. Sub-tuberculate above, striate [instead of sulcate] 
below. Perhaps the form described by Smith, 1. c., as found by 
Brazier at the Marshall Islands. 
var. [? dist. sp.]. 
Long. 3, diam. 22 mil. Differs from the Arakan form of 
R. isseli by the still narrower perforation, more convex base, 
with more regular and more numerous spiral sulcations. 
8 Cherboniane Reef; coll. Dr. J, Armstrong. 
2 Mauritius; ex c. Dr. F. Stolizcka [in bad condition ; identification 
doubtful]. 
var. subinfracostata [? dist. sp.]. 
Probably distinct; the specimens have their opercula, but 
are perhaps not quite adult? Descr. de l’Egypte, Pl. V, fig. 40, 
gives a good idea of them. It is perhaps rather a var. of that 
species, L. infracostata, Issel ? 
3 Nicobar Islands; coll. Dr. F. Stoliezka. 
6. Risella [Peasiella] conoidalis. 
Trochus conoidalis, Pease, Amer. Journ. Conch. ITI, 1867, Paumotus; alt. 6, 
diam. 4 mil. 
3 Paumotus [typical]; coll, H. Pease, Esq. 
4. Risella [Peasiella] infracostata. 
Risella infracostata, Issel, Malac. Mar Rosso, 1864, Suez and Desc. de 
V Egypte, pl. V, fig. 40. 
6 Massaua ; coll. Prof, A. Issel. 
Sent me as “Troch. sismonde, Iss.”, probably a lapsus 
calami ? Iam inclined to believe it can only be separated from 
the following as a variety; my Aden specimens seem a fairly 
intermediate form. 
8. Risella [Peasiella] isseli. 
Risella isseli, Semper, Issel, Malac. Mar Rosso, 1864, Suez and Zunzt- 
bar; Descr. del Egypte, pl. V, fig. 35. 
