BIVALVIA. 
Moll 87 
Pecten hoshynsi (Forbes) = imhrifer (Lov^n), vitreus (Chemn.), ahys- 
sorum (Loven), and grcenlandicus (Sow.), Arctic Norway ; id. 1. c. 
pp. 20-23, pi. ii. figs. 1, 4, 5, & 6. 
Spondylus varius [varians (Sow.)] has internal holes in the larger 
valve, from periodical removal of the mantle, but at the spot where the 
adductor muscle is inserted, the shell remains continuous ; Owen, P. Z. S. 
1878, p. 967, woodcut. 
Spondylus wrightianus (Crosse, 1873), Wright, List of shells for sale, 
p. 75, pi. ix. 
OSTREIDJ). 
The common Oyster occurs from the Bay of Biscay to the Shetland 
Islands, Bergen in Norway, and the Kattegat, in fact, on the shores of 
Europe that are touched more or less directly by the Gulf Stream ; there 
is a degree of admixture of fresh water in which it is able to live and 
thrive, though unable to propagate, attaining a size and delicacy which 
could not be reached, if any part of the vital power were to be spent on 
propagation ; this is important in considering the localities for artificial 
oyster banks. Winther, Ann. N. H. (5) i. pp. 185-189. 
Guiquel publishes a translation of a Chinese treatise on oyster breed- 
ing ; Bull. Soc. Acclim. 1878 (March), 8 pp. 
Ostrea cristata (Born) = plicata (Chemnitz, Reeve), not the Mediter- 
ranean species taken by Philippi and othei*s for it ; Brauer, SB. Ak. 
Wien, Ixxvii. Abth. i. p. 140. 
Ostrea assuming the sculpture of another shell, Trochus maculatus, to 
which it adheres; E. A. Smith, P. Z. S. 1878, p. 730, pi. xlvi. fig. 12, 
[Similar instances are common in Anomia^ 
A^tomiTym. 
Anomia. The two muscles going from the left valve to the so-called 
plug are considered by H. v. In bring as two portions, a muscular and a 
ligamentous one, of the posterior retractor pedis; at the root of the 
plug there is a “ plaited organ hitherto not described, forming part of 
the body, and covered by a layer of epithelium ; the plug itself shows a 
lamellar structure. The plug and plaited organ may be compared to the 
byssus and byssal glands of other Bivalves, though differing in their uni- 
lateral situation on the right side, which, perhaps, is to be explained by 
shifting in the young stage. Z. wiss. Zool. xxx. suppl. pp. 13-15 & 
19-26, pi. ii. figs. 1-6 & 9. See also Coutance, in the general subject, 
supra, p. 9. 
Anomia aculeata (L.), a distinct species, Norway, in shallow and deep 
water ; G. 0. Sars, Moll. arct. Norveg. p. 15, pi. xix. fig. 1. 
