172 
MOLLUSCA. 
a very young shell; in which the summits are above the anterior end, as in 
Modiola. 
Modiola atenima, sp. n., Dali, Am. J. Conch, vii. p. 164, Bay of Yeddo. 
Modlolaria discors (L.), niffra (Gray), and marmorata (Forbes), from Kiel : 
Meyer & Mubins, 1. c. ii. pp. 78-84, pi. 12, figs. 4-0, 1-3, and 10-13. 
M. doiUivtdata, sp. n.. Dull, 1. c. p. 164, Acapulco. 
AviCULIDiE. 
Avicula is monographed (in Kuster^s new ed. of Martini & 
Chemnitz) by Prof. W. Dunkek, who introduces a number of new 
species (rather too many for a genus, the species of which are so 
variable), but maintains as identical the pearl-oysters of the 
Indian aiid Caribbean seas, under the common name A. mar- 
gai'itifera (L.), the older literature of which is more fully quoted 
than the recent. The figures are partly original. The new 
species and those figured for the first time are : — 
Avicula acheepmakeri^ sp. n., p. 6, pi. 1. f. 1 ; reentsi, sp. n., p. 9, pi. 2. figs. 1 
«& 2, Red Sea; Uchtmsteini (Dkr.), p. 10, pi. 2. f. 3, Sandwich Islands; hoi'riduj 
sp. n., p. 11, pi. 2. f. 4, Venezuela ; grisea, sp. n., p. 11, pi. 2. f. 6; longisquamosUf 
sp. n., p. 12,pl.2. f. 0, Venezuela; hadia (Dltr.), p. 12, pi. 2. f. 7)Jimhvuila (Dkr.), 
p. 13, pi. 3. f. 2 & G, Central America; atripurpuvea (Dkr.), p. 14, pi. 3. f. 3; 
cUrina (Dkr.), p. 14, pi. 3. f. 4 ; tamsiana (Dkr.), p. 15, pi. 4. f. 1 & 2, Venezu- 
ela ; oHvacea, sp. n., p. 17, pi. 4. f. 5, Antilles ; varia, sp. n., p. 17, pi. 4. f. 6, Red 
Sea; serrulata (Dkr. isks)=.lata (Gray, in Reeve, 1857), p. 18, pi. 5. f. 1 & 
2, Moluccas ; venezuelensis, sp. n., p. 19, pi. 6. f. 3, Venezuela ; nigrifusca^ 
sp. n., p. 20, pi. 5. f. 4 ; peasii, new name for radiata (Pease, nec Leach, nec 
Phil.), p. 24, pi. 8. f. 1, Kingsmill Islands; physoides (Lam.), p. 25, pi. 8. 
f. 2 & 3, West Australia ; cypsellus, sp. n., p. 26, pi. 8. f. 4, Indian sea ; stra- 
minea (Dkr.), p. 20, pi. 9. f. 1, Indian seas ; cochenhausi, sp. n., p. 27, pi. 9. f. 3, 
China ; spadicea (Dkr. 1862) = re<ii7« (Reeve), p. 31, pi. 10. f. 1 & 8, Red Sea; 
hyalina (Dkr. \B>ii2)=iS(ndpta (Reeve), p. 32, pi. 10. f. 3 & 4, Tasmania ; ja- 
ponica (Dkr.), p. 33, pi. 10. f. 6, Japan ; cornea (Dkr.), p. 3-3, pi. 10. f. 6, loca- 
lity unknown ; tortirostris (Dkr.), p. 37, pi. 11. f. 6, Java ; tristis, sp. n., p. 44, 
pi. 14. f. 3 ; reeviana) new name for Jimhriata (Reeve, 1867, nec Dkr. 1852), 
p. 45 ; pallida^ sp. n,, p. 49, pi. 16. f. 4 ; gruneri, sp. n., p. 51, pi. 18. f. 1 ; con- 
cinna^ sp, n., p. 52, pi. 18. f. 2 ; prasina, sp. n., p. 63, pi. 18. f. 4 ; atrata, sp. n., 
p. 55, pi. 19. f. 1 ; hi'cvialatUy sp. n,, p. 55, pi. 19. f. 3, Amboina ; pUcatula (Dkr.), 
p. 50, pi. 19. f. 4. In all, 71 species, of which 32 are named by Dunker 
himself, 28 by Reeve, and only 11 by other authors. 
Perna hawaiiensisy new name for calif ornica (Conrad), which implies an 
erroneous locality ; Pease, Am. J. Conch, vii. p. 25, 
OSTREACEA. 
Arcidas. 
Scapharca j^ygnicea, sp. n,, 11. Adams, P. Z. S. 1872, p. 11, pi. 3. f. 15, Red 
Sea. 
