MOLLUSCA. 
641 
PLANAXIDiE. 
Planaxis nicoharicm (Zelebor), Reis. Novar. Moll. pi. 2. fig. 1. 
Rissoellid^. 
This family is established by Clark^ tinder the name of Hetero- 
phrosynid( 2 j 2 in.di accepted by Jeffreys (Brit. Conch, iv. pp. 55-63), 
on account of the operculum having an excentric nucleus like 
that of Buccinum and an internal process analogous to that of 
Neritina. It comprises the following two genera : — 
(Clark). Snout and eyes as in j shell solid and smooth. 
One British species, rubra (Mont.)=/«/fa (Mich, as Bmod) j varieties uni- 
fasciata (Mont.) and pallida. 
Jeffrey sia (Alder). Snout deeply cloven; eyes behind the tentacles; shell 
thin, smooth, and glossy ; lingual armature as in Rissoa. Three British spe-, 
cies: diaphana (Alder), opa/ma (Jeffr.), glohularis (Jeffr.). 
Rissoid.®. 
Iravadia, g. n., Blanford. Testa imperforata, turrita, spiraliter costata, 
solida, epidermide tecta; apertura ovata, Integra, antice obsolete efFusa; 
peristomate recto, extus variciformi-incrassato, intus dilatato. Differs from 
Rissoma by the epidermis, the spiral sculpture, and the peristome being nei- 
ther sinuated above nor projecting below, and in the columellar margin 
being simply chrved in front and not excavated, from Hydrohia and Aninicola 
by the variciform peristome. Operculum unknown. I. ornata, sp. n., Myit- 
taya, a branch of the Bassein river, delta of the Irawady in salt water. Blan- 
ford, Journ. As. Soc. ii. p. 66, pi. 2. figs. 13, 14. 
Jeffrey sia ? translucens, sp. n., Carpenter, Proc. Calif. Acad. Nat. Sc. 1866 
p. 219, San Diego, California. 
Rissoina frauenfeldif sp. n., Schwartz v. Mohrenstern, Reis. Novar. Moll, 
p. 10, pi. 2. fig. 13, Port .Jackson ; R. media of the same author, found pn 
the Nicobar Islands ; R. hanleyi, at Sydney, by the same expedition, ibid., 1. c. 
Rissoina variegata, turricula^ smithi, and cincta, spp. nn., Angas, Proc. Zool. 
Soc. 1867, pp. 113, 114, pi. 13. figs. 19-22, Port Jackson. 
Rissoma semipUcata (Pease, Proc. Zool. Soc. 1862), gracilis, costulata, tenui- 
striata, striatula, scmicostata, spp. nn., Pease, Am. Journ. Conch, iii. pp. 296, 
296, pi. 24. figs. 27-32, Paumotu and Caroline Islands. — Rissoina interfossa^ 
sp. n.. Carpenter, Proc. Calif. Acad. Nat. Sc. 1866, p. 217, California. 
[^Rissoina'] Rissoa zeltneri, sp. n., Folin, M^l^agrinicoles, p. 47, pi. 6. fig. 1, 
on pearl-oysters from Panama. 
Putilla, g. n., A. Adams. Shell smooth, solid, with thickened lip. — P. lu- 
cida, sp. n., Gotto Islands, Japan, in 64 fathoms. A. Adams, Proc. Zool. Soc. 
1867, p. 312, pi. 19. fig. 312. 
Gyriscus, g. n., Tiberi, Journ. Conch, xv. p. 302. Testa turbinata, conico- 
turrita, umbilicata ; apex obtusus, vertice involute ; anfractus rotundati, trans- 
verse cingulati ; apertura subcircularis, marginibus acutis, callo junctis, co- 
lumellari reflexo. Operculum corneum, superne multistriatum, inferne pro- 
cessu styliformi praeditum. Animal unknown. One species, G. Jeffreysianus, 
Bp. n., Sardinia, on corals. [Near Rissoina ?~\ 
Fenella pupoides, sp. n., Carpenter, Proc. Calif. Acad. Nat. Sc. 1866, p. 217, 
Monterey. 
