1882.] 
P. 563. 
‘LIGHTNING’ AND ‘ PORCUPINE’ EXPEDITIONS. 683 
Lima subovata. Between Lisbon and Canaries (‘Tra- 
vailleur’ Exp. 1882); 1192 fms. 
P. 564. Lima subauriculata. Between the Hebrides and Faroes 
rr 
ao 
(=>) 
© 
(‘ Triton’ cruize); 570fms. Josephine Bank ; 110- 
120 fms. 
Lima excavata. Fossil. Pliocene: Calabria (Seguenza) ! 
. Mytilus incurvatus. Probably a Pliocene fossil of the 
Bolognese, as Modiola rectemarginata of Foresti. 
Mytilus phaseolinus. Black Sea (Spratt) ; 45-50 fms. 
Dacrydium vitreum. Between the Hebrides and Faroes 
(‘ Triton’ cruise); 570 fms. Azores (‘ Josephine 
Exp.); 200-300 fms. 
. Idas argenteus. Between the Hebrides and Faroes 
(‘ Triton’ cruise); 516 fms. Inhabiting deserted 
tubes of Teredo megotara in a large water-logged 
piece of pine-wood, to which the Jdas had fixed 
itself by a strong byssus. It is covered with a pale 
brownish-yellow epidermis, which rises into fibrous 
excrescences on the posterior side. Under the epi- 
dermis the shell is silvery white. An internal and long 
cartilage covers the hinge. I was mistaken as to this 
when I described the species from two small valves. 
The beak has a reddish colour like that of Cypricardia 
lithophagella. The shape varies from rhomboidal to 
oblong. Size of my largest specimens 33 tenths of an 
inch or about 8 millimetres. With it in a ‘‘commen- 
sal’’ way lived an undescribed species of Coceulina, or 
a new genus of the same family, to which I propose 
giving the name of spinigera; this would seem to have 
fed on decomposed portions of the Z'eredo. Small 
Aunelids also occupy the tubes and probably have the 
same habit. The little limpet is coated with a cera- 
tose sponge, which gives it a prickly appearance. 
The smaller and younger specimens of Teredo were 
living when the piece of wood came up in the trawl. 
Idas argenteus is probably the species of that name 
noticed by Verrill as var. damellosa, from 337 fathoms 
off the coast of New England. 
Arca barbata. C. Verd I. (de Rochebrune). 
Arca nodulosa. Fossil. Miocene: Marne Vaticano 
(Ponzi). : 
Arca tetragoaa. CO. Verd I, (de Rochebrune). 
Arca antiquata, C. Verd I. (de Rochebrune). 
Arca obliqua. Josephine Bank, 340-430 fms. 
Arca glacialis. G. Mexico (Dall)? 
Arca pectunculoides, var. septentrionalis. New England 
(Verrill); 310 fms.! Between the Hebrides and 
Faroes (‘ Triton’ cruise); 570 and 608 fms. Medi- 
terranean (Italian Exp., 1881) ; 337-464 fms. 
