206 Dr. E. von Martens on some Species of Assiminea. 
d. Species from the Pacifie Islands. 
1. Without keel. 
A. albescens (Hydrocena albescens, Pfr. Pneum. Suppl. p. 157). 
Opara. Cuming’s collection. 
A. solidula (Hydrocena solidula, Pfr. 1. c.). Lord Hood’s 
Island. Cuming’s collection. 
A. ventricosa (Cyclostoma ventricosa, Hombron & Jacquinot, 
Voy. au Péle Sud, pl.12.f.34-86. Realia ventricosa, Pf.). Otahiti. 
Alhed to A. Charreyi. 
2. A keel round the umbilicus. 
A, rosea (Cyclostoma rosea, Gould, Exped. Shells, p. 39. Om- 
phalotropis rosea, Pfr. Pneum. p. 308). Fiji Islands. Cuming’s 
collection. 
A. bulimoides (Cyclostoma bulimoides, Hombron & Jacquinot, 
Voy. au Pole Sud, pl. 12. f.37-89. Hydrocena bulimoides, Pfr. 
Pneum. Suppl. p. 162). Caroline Islands. Cuming’s collection. 
A. dubia, Pfr. Zeitschrift f. Malakozoologie, 1847, p. 112. 
(Omphalotropis dubia, Pfr. Pneum. p. 310). Opara. Cuming’s 
collection. 
A. huahemensis (Hydrocena huaheinensis, Pfr. Pneum. p. 163). 
Huaheine. 
A. maritima (Hydrocena maritima, Montrouzier; Journ. Conch. 
x1. pl. 5. fig. 4). New Caledonia. 
Also Realia producta, abbreviata, and fragilis (Pease), from 
the Sandwich Islands (Cuming’s collection), 1 suppose to belong 
to Assiminea. 
e. Species from the North Pacific beyond the Tropics. 
Laguncula pulchella, Benson (Ann. & Mag. Nat. Hist. 1842, 
ix. p. 488), found at Chusan by Dr. Cantor, may perhaps 
be an Assiminea. I suspect this to be the case from the words, 
“ peristomate interrupto, labio subreflexo, umbilico profunde tor- 
tuoso,” and “ apertura intus fascia lata pallide castanea ornata.” 
This coloration calls to mind the Siamese Assiminea maculata. 
The sculpture, however, and the deep suture are not favourable 
to this supposition. The locality given is, “said to inhabit 
canals.” The same words are repeated for Bullea caurina, Arca 
galactodes, Mytilus niger, Dreissena purpurascens (evidently a Sep- 
tifer near bilocularis, Li.), Venus sinensis, Sanguinolaria iridescens, 
and Novaculina constricta,—all marine or brackish-water shells ; 
whereas, for the true freshwater shells Planorbis, Limneus, Palu- 
dina, the locality is given with much more assurance and detail. 
From this we may perhaps be led to suspect that Laguncula pul- 
chella habits the same localities as Novaculina, Venus sinensis, 
&e.; and as the two last-named are common in the brackish 
