MOLLUSCA. 
585 
sulcata (G\'^ij)=^erythr(ca (Jonas) (Hanl.) &c., paralytica^ sp. n., 
Madagascar, rohillardi (Bernardi), unclata (Dunker), and minima (Montdgu) 
— triangularis (Montagu) are accurately described and beautifully figured 
by E. Roemer, Monograph Veyius, pp. 191-215, pis. 52, 63. 
Venus (subgenus Cytherea, sectio Crista). C. pectinata (L.), gihhia (Lam.), 
menkei (Jonas), adunca, sp. n., Indian Seas, ecquivoca (Ohemn.), cuneata 
(Lam.), divaricata (Ohemn.), discors (Spengler), dispar (Ohemn. 
(hm)..)—marmorata (Reeve), ahhrcviata (Lam.), transversaria (Desh.), and 
nummulma' (Lam.) are accurately described and figured by E. Roemer, 
Monogr. Venus, pp. 172-189, pis. 47-61. 
Vmus (Lioconcha) arahica (Ohemn.). Its varieties of colour pointed out 
by Issel, Malac. mar. ross. p. 66. 
Cytherea meretrix (L.), including as varieties lusoria (Ohemn.) =/ormosa 
(Sow.) qxsA petechialis (Lara.), common at Japan, fully described by Lischke, 
MoU. Jap. pp. 122-126; it is eaten by the Japanese, and used in a simple 
game by them. A. Adams, Ann. & Mag. Nat. Hist. iii. p. 229. 
Cytherea mediterranean sp. n., Tiberi, is perhaps a variety of C. rudis (Poli) ; 
previously indicated, but not yet sufficiently described, by Petit, Oatal. Moll. 
Eur. p. 250. 
Venus. On the variations of V. casina and fasciata, and on V. cygnus, 
which is distinct from V. mvltilamclla, see Petit, I. c. pp. 250-262. 
Venus roemeriana, sp. n., Issel, Malacol. mar. ross. p. 64, figured but not 
described by Savigny, Descript, de I’Egypte, Ooquilles, pi. 8. fig. 3, Suez. 
Liocyma, gen. nov. Shell trigonal or elongate-ovate, with concentric un- 
dulations and a polished epidermis ; pallial sinus small, rounded, triangular ; 
three teeth in each valve, divaricate; lunulo faint, no areola; ligament set 
in below the exterior surface. Soft parts described in detail. Type Venus 
Jluctmsa (Gould), in Massachusetts ; another species is now, viz. X. heckii, 
from Plover Bay, East Siberia, and Alashka. Dali, Proc. Dost. Soc. Nat. 
Hist. xiii. pp. 266, 267. — V. Jluctuosa (Gould) found at Hammerfest, Norway. 
Petit, Catal. Moll. Eur. p. 362. 
Crassivenus is a new generic name proposed for Mercenaria (Schumacher, 
1817) by Perkins, Proc. Bost. Soc. Nat. Hist. Dec. 1869. 
Totteniana, afterwards corrected into Tottenia, is a new generic name for 
Venus gemma (Totten) proposed by Perkins, 1. c. [already named Gemma by 
Deshayes, Cat. Brit. Mus.]. 
Tapes philippinarum (A. Adams and Reeve), including as varieties indica 
(Hanley), (Desh.), and ? denticidata (Sow.), very near to decitssata 
(L.), common in Japan, fully described by Lischke, Moll. Jap. pp. 115-118. 
Tapes euglyptus (Phil.) described by Lischke, ibid. p. 119. 
Saxidomus purpuratus= S. nutalli (Schrenck) = <S'. giganteus (Desh. ?, Mar- 
tens), described by Lischke, 1. c. pp. 127-129, pi. 9. figs. 4, 6. 
Clementia (Gray). The history and characters of this genus are discussed 
and three species distinguished by Dr. L. Pfeiffer, viz. p>apyracea (Gray), 
vitrea {Oh^mmiz), and hyalina (Phil.); no locality is given. Mai. Blatt. 
xvi. pp. 190-194. 
PETRICOLIDiE. 
Petricola hemprichii, sp. n., Issel, Malacol. mar. ro.ss. p. 61, pi. 1. fig. 6, 
Suez. 
1869. [voL. VI.] 2 s 
