396 
har ,, Ingolf" faaet talrige levende Eksemplarer paa adskillige 
Stationer indenfor det nævnte Havomraade, men ingensteds paa 
Dybder, der ere mindre end 124 Favne eller større end 495 Fv. 
Denne Form gaar derfor næppe ned til de 1003 eller 1309 Fv., 
og omvendt holder den sig paa saa stort Dyb, at den er uden 
for Isens Rækkevidde. .... Denne Bivalv er nemlig, mig be- 
kendt, ikke taget paa Dybder, der ere mindre end 40 Fv. 
(Kara Havet), og som oftest holder den sig meget dybere”. 
2) The occurrence of dead shallow-water shells at great depths in 
the North Polar Basin is a very common phenomenon. The 
shell-transportation by means of floating ice is, on the contrary, 
rather unimportant. The theory of transportation therefore does 
not give a sufficient explanation of the frequent -occurrence of 
these peculiar molluse-forms. (Fr. Nansen l.c. W. Brøgger 
l.c. A.$. Jensen 1.c.. 1900.) 
”3) The found shells of bivalves are undamaged and can often be 
matched; moreover now and then they are united by a part 
of the ligament or by the hinge. If the shells had been trans- 
ported by the ice they might not be supposed to have been so 
well preserved (ÅA. S. Jensen l.c. 1900 p. 231 & 232). 
4) The area on which these dead shallow-water shells are deposited 
has a well marked limitation. In those parts of the Atlantic 
south of the submarine ridges Færoe-Iceland and Iceland- 
Greenland, as well as in the Davis Strait, a similar occurrence 
of shallow-water shells at great depths does not exist, what 
might be expected if the occurrence was a result of transporta- 
tion by floating ice (A. S. Jensen. 1900. 1. c. p. 237). 
To the first point the following objection may be set forth: 
A.S, Jensen's statement that Portlandia intermedia does not occur 
at lesser depths than at 40 fms. is without doubt incorrect. Leche 3 
1) W. Leche: ,Ofversigt åfver de af Vega-Expeditionen insamlade arktiska 
hafsmolluskér", Vega-Expeditionens vetensk. Iagtt. Bd. 3. Stockholm 
p. 446. i 
