KUNGL. SV. VET. AKADEMIENS HANDLINGAR. BAND 52. N:o |6. 13 
2. Molluscea from the Pearl Banks off Cape Jaubert. 
a. Lamellibranchia. 
FAM. LIMIDABE. 
Lima squamosa LAMARCK. 45 miles W. S. W. off Cape Jaubert, 48—60 feet 
(GuLLSTSps, max. 1. 42 mm; 42 miles W.. Si wW., 00-721 teet" (""/7), & sps, max. 1. 23 
mm. — The present specimens differ from the Mediterranean form only in somewhat 
feebler longitudinal ribs and smaller scales. MELVILL & STANDEN (1899) trace the 
species from the regions of the Indian Ocean to Torres Straits: »We have traced 
it across the Isthmus of Suez to Red Sea waters, then along the coasts of India 
and Ceylon, eastward, uninterruptedly» (p. 182). In the collections of the Swedish 
State Museum the species is represented from Singapore and Osaka. Also LYNGE 
(1909) records it from Singapore. BE. A. SmirH (1885, Rep. Challenger) mentions it 
from the Philippines, the Louisiade Archipelago and New Zealand, and LIscHKE 
discusses its distribution in Japan. 
L. fragilis CHEMNITZ. 42 miles W. S. W., 42 feet ("/7), 1 sp., 1. 8.5 mm; 45 
miles W. S. W., 70—72 feet ('"”'"/1), 4 sps, max. 1. 12.5 mm. — The species has a 
wide distribution from Suez and Persian Gulf to the Philippines, and the Society 
Islands (LYNGE 1909; MELVILL & STANDEN 1906, v. MARTENS 1886); W. Australia 
(HEDLEY 1916). 
FAM. OST REIDAFE. 
Ostrea vitrefacta SowErBY. 45 miles W. S. W., 72—80 feet (”''/), many sps, 
max. 1. 12 mm, from spines of Echinids. In shape the specimens resemble O. mytil- 
oides LAMARCK (REEVE, Conch. Icon. 18, fig. 3), but as the shell borders are set 
with teeth all round as in specimens of O. wvitrefacta from Madagascar which have 
been compared, the present form may be considered identical with that species. 
From their attached position on the Echinid spines they have acquired a stretched 
form, tapering towards the apex. — The species is previously known from Mauritius 
(REEVE, Conch. Icon. 18, 1871). 
0. rivularis (GoUuLp) LiscHKE. 42 miles W. S. W., 70—72 feet (”"/s), many 
sps, max. Il. 18 mm; 45 miles W. S. W., 48—72 feet, 4 sps, max. Il. 20 mm. LYNGE 
(1909) mentions the species from Gulf of Siam. It is, besides, known from Japan. 
0. imbricata LAMARCKE. 45 miles W. S. W., 66 feet ("?/s), 1 sp., 1. :100 mm. 
It shows in the colour (light reddish spots and stripes) and in its sculpture (radiating 
ridges here and there rising to tubular scales) close agreement with figure 36 in 
REEvE's Conch. Icon. 18, 1871. LYNGE (1909) considers it to be a variety of O. 
hyotis and gives its distribution from the Persian Gulf to Japan, Java, and New 
Guinea; it occurs also on Queensland (HEDLEY 1910). 
