46 RISSOIDE, 
18. Stenothyra, sp. 
1 Java (?); coll. Baron F. von Richthofen. 
Not the species figured by Mousson. 
19. Stenothyra woodmasoniana. 
Stenothyra woodmasoniana, @. Nevill, J. A. S. B. 1880, Pt. Canning, long. 
81, diam. (viv) 2 mil., and op.c., 1881, pl, VII, fig. 8.- 
10 Port Canning (type) ; coll. J. Woo0d-Mason, Esq. 
4, Family RISSOIDA, Gray. 
Subfamily HYDROBIINZ, Troschel [emend.}. 
Genus HYDROBIA, Hartmann. 
Sturm, Fauna Deutschland, 1821, types H. acuta, vitrea, and minuta [sine 
descr.| ; type restricted Hydr. acuta, Drap., Fischer, J.de C. 1878; = 
Paludestrina, Orb.-( pars), Voy. Amer. Merid. 1889, p. 381, type P. nigra, 
Orb. Se. ;==Eecrobia, Stimpson, 1865, type Turbo minutus, Totten ; = Lit- 
torinella, Braun, 1842, and of Thomae, Jahrb. Ver, Naturh, Nassau, II, 
p. 125, 1845, type Hydr. acuta, Drap.;=Peringia, Palad., Ann. Sci. 
Natur, 1874, type H. ulvae, Mtg.; sect.=Thermhydrobia, Paulucei 
1878, type Hydrobia aponensis, v. Martens. 
The animal of Hydrobia [as “ Littorinella’”] is generically 
distinct from that of Peringia [as “ Hydrobia’], according to 
Stimpson. Gray, in Turton’s Manual, 1840, proposed Turbo 
ulvae, Pennant, as type of the genus, but this cannot, however, 
be so accepted, because it was not one of Hartmann’s original 
type species. 
1. Hydrobia ulvee. 
Turbo Ulvae, Pennant, Brit. Zool, 1776; fide Jeffreys Pal. muriatica, Lam, 
and [p. 310}=Oyel. anatinum, Drap. ; fide Mirch, 1871=H, Jeverensis, 
Schroter, with var. grandis, from Denmark, long. 94 mil. 
20 Shorcham and Weymouth ; coll, G, Nevill and T. F, Nevill, Esqrs, 
