16 Moll. 
MOLLUSCA. 
Numerous observations on the biology, adaptation to soil and water, 
variation, &c., of the European land and fresh- water J/o^^wsca, with hypo- 
theses concerning their phylogeny, by F. Hazay, Mai. Bl. (2) iv. 
pp. 43-221. The iifetime of Vitrina is probably only 1 year; that of 
Hyalina nitens^ years (pp. 115 & 11 G) ; of [lelix j)omatia G-8 ; of 11. can- 
dicans 2-3 (pp. 117 & 118) ; Paludina 8-10 ; Limncca and Planorhis 3-4 
(p.73). 
H. Jordan discusses the variations of shape in several species of Euro- 
pean Unionidee, with regard to the localities in which they live ; speci- 
mens from rivers have generally a heavier shell, and are more thickened in 
front and more lengthened and sometimes bent downwards at the hinder 
end, in comparison with those from lakes ; the cardinal teeth become 
stronger and the muscnlar impressions deeper where the water is much 
agitated ; rays of green colour are found only in specimens from rivers, 
&c. Biol. Centralbl. i. pp. 392-399. 
Some instances of association of fresh-water shells by Butterell, 
J. of Conch, iii. p. 177. 
Thermal springs of 20^-26° near Buda-Pest; the common fresh-water- 
shells, as Bythinia tentaculata, Planorhis maryinatus, and Limncca lagotis 
remain in them remarkably smaller than elsewhere. Limncca peregra 
alone is plentiful and of ordinary size. Hazay, Mai. Bl. (2) iii. p. 7. 
Land and fresh-water snails perish when exposed to — 7° to — 10 °C. for 
half-an-hour or somewhat longer, or to — 5° C. for two days ; those of 
larger size resist somewhat longer, young specimens of the same perish 
at — 4° C. or less ; Bodel, “ tlber das vitale Temperatur-minimum 
wirbelloser Thiere,'* Diss. inaug. Halle : 1881, pp. 11-14 & 34. 
Helix aspersa living 13 months without food ; Lockwood, Am. Nat. 
xiv. [1880] p. 214. 
Some specimens of Limncca survived a dessication of about two months; 
J. L. Hawkins, Sci. Goss. 1881, p. 23 ; J. of Conch, iii. p. 181. 
H. Leder has observed that Daudebardia lederi produces a strange 
feeling, somewhat like that of electricity, in the hand of man ; Bottger, 
JB. mal. Ges. viii. pp. 27G & 277. 
Instance of a snail recognizing and distinguishing the human voice ; 
W. H. Ball, Am. Nat. xv. pp. 97G & 977. 
Land snails broken and eaten by thrushes ; Ashford, J. of Conch, iii. 
p. 134. 
A large number of the young of Succinea putris swept from their - 
winter moorings by a flood, and destroyed by insects ; id. 1. c. pp. 195 & 
19G. 
The rather frequent occurrence of larvae of Distomidcc in terrestrial 
snails, stated by G. Ercolani ; Mem. Ac. Bologn. (4) ii. 
12 . Abnormities. 
Several monstrosities of marine shells; Tryon, Man. Conch, iii. 
pp. 112 & 113, pi. xliv. figs. 238-242. 
15-25 specimens per thousand of Melantho are sinistral, if the 
