296 Mr. A. Alcock on the Bathyhial Fishes 
and Gastropod and Lamellibranch Mollusks ; besides some 
curious green-coloured Fucus-Wke, ova (?) adherent to the last. 
By the Laccadive Sea is meant the basin which intervenes 
between the west coast of India and the parallel series of 
ridges whose peaks form the bases of the shoals and atolls of 
the Laccadive Archipelago. 
It is a long narrow basin, open to the south and closing in 
gradually to the north, its boundary here being the Angrias 
Bank, in lat. 16° 30 ; N. It slopes steeply from east to west, 
its greatest depths, which are not much over 1100 fathoms, 
being close to the Laccadive Islands, which individually rise 
abruptly from the bottom. The nature of the bottom on the 
Indian side is, as would be expected, determined by detritus 
from the land ; but on the Laccadive side the bottom consists 
almost entirely of coral-mud, with a variable proportion — from 
2 to 12 per cent. — of Foraminifera shells. 
§ 2. Notes on the Fishes , with Descriptions of new Species . 
The bathybial fishes collected in the Laccadive Sea are 
remarkable for their large size. 
At twenty stations in the Bay of Bengal and neighbouring 
waters the c Investigator ’ has taken deep-sea fishes ; and on 
contrasting them with these from the Laccadive Sea, the 
superior bulk of the latter is strikingly manifest. Among 
the Macruri , comparing mature females, the two specimens 
from the Laccadive Sea measure respectively 22 and 19^ 
inches, and weigh respectively 1*5 and *65 lb. ; while the 
two largest specimens from the Bay of Bengal measure 
respectively 14£ and 11 inches, and weigh respectively *23 
and T5 lb. The Ophidiids from the Laccadive Sea are 
also larger and heavier. Again, the longest deep-sea Phy- 
sostome taken in the Bay of Bengal measures but 16 inches, 
against the 21 inches of the longest Physostome from the 
Laccadive Sea ; while the average length of the Bay of 
Bengal specimens of this suborder is under 9 inches, against 
an average length of nearly 14 inches of the Laccadive Sea 
specimens. 
The occurrence in the deep w T aters of the Arabian Sea of 
forms hitherto known from the depths on the one hand of the 
Mid-Atlantic, and on the other hand of the North Pacific, is 
a further illustration of the wideness of distribution of true 
bathybial fishes. 
The following is the list of the fishes 
