418 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
with their specimen, but the authors have been unable to see the German 
naturalist’s description of Megateuthis martensi. 
B. Pteropoda. 
Pteropoda of the ‘Albatross’ Expedition.* — Mr. J. I. Peck reports 
on the Pteropods collected by the £ Albatross ’ during the journey from 
Norfolk, Va., to San Francisco, Cal. Of the three families of the 
Thecosomatous Pteropods the Limacinidae are represented only by two 
live specimens of Limacina inflata , which were taken at a depth of 
880 fathoms. This would agree with Haeckel’s statement that this par- 
ticular species is one of those belonging to zonary and bathybial faunae, 
'(’he Cymbuliidne are not represented in the collections at all. The 
Cavoliniidae are represented quite completely both at surface and bottom. 
There appear to be no marked distinctions between the kinds and distri- 
bution in the Atlantic and Pacific waters upon either side of northern 
South America. The shells in deposits confirm the evidence of the 
surface collections, so far as there is any evidence from deposits from 
the ocean floor. The author gives various’ notes on the species which 
were collected. 
y. Gastropoda. 
Heteropoda of the ‘ Albatross ’ Expedition.! — Mr. J. I. Peck has 
a short notice of the Heteropods collected during the voyage of the 
‘ Albatross ’ around South America. But little material was obtained, 
though the individual specimens are, in nearly every instance, beautiful 
representatives of the various genera of this widely distributed group. 
Atalanta , Carinaria , and lanihina were found. Of the third genus, all 
the specimens taken were found within a few degrees of the Equator. 
Formation of Snail Shell.! — M. Moynier de Villepoix explains that, 
when in 1891 he described the formation of the shell in Helix as due to 
a pallial gland ( bandelette palleale) which secreted lime and organic 
matter, he was unaware that MM. E. Mer and Longe had described this 
in 1880 under the name of coin epithelial. They have therefore priority. 
The author finds the same shell-making gland in Paludina vivipara and 
other aquatic Gasteropods. 
5. LamellibrancMata. 
Seat of Coloration of Brown Oysters.§ — M. J. Chatin, who has 
already studied green oysters and shown that their coloration is situated 
in special cells, the macroblasts, which are chiefly in the apical region 
of the branchial papillae, has now made a study of brown oysters, and 
finds that here too it is the macroblasts which are the site of the brown 
coloration. If one takes an oyster in which a brown colour is beginning 
to appear, one finds that most of the macroblasts are still colourless, 
and the protoplasm of the cells is diaphanous and homogeneous ; the 
nucleus is very apparent, and is large and spheroidal. Little by little 
this appearance changes, at first the periphery of the cell, and then the 
circum-nuclear zone become altered, for granulations become visible even 
* Proc. U.S. Nat. Mus., xvi. (1894) pp. 451-63 (3 pis.). f Tom. cit., pp. 463-5. 
x Comptes Rendus, cxx. (1895) pp. 512—3. § Tom. cit., pp. 884-7. 
