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Scientific Memoirs by

      The newly-hatched larva of this Loricate, as I observed it in the month of
January, is a Phyllosoma 1/12th of an inch long. Its body is divided into three
regions, namely (1) a broad crescentic cephalo-thoracic portion, (2) a postero-tho-
racic portion, with posteriorly convergent sides, consisting of five distinct seg-
ments, and (3) a very short stump-like abdomen bearing a pair of foliaceous,
lobes at its abruptly-truncated end.

      The appendages (including buds) of the anterior region are a pair of huge
long-stalked pyriform eyes, two pairs of antennæ, a pair of toothed mandibles,
three pairs of small papillæ—the buds, respectively, of the two pairs of maxillæ
and first maxillipeds—and lastly two well-formed pairs of apparently five-jointed
maxillipeds.

      The middle region carries five pairs of very elongate legs, the first of which
seems to be five-jointed and uniramous, while the other four are six-jointed and
biramous.

      The abdomen has no appendages, unless the terminal lobes are such.

      (c ) The larva of the deep-sea lobster Nephrops andamanica, when removed
from the egg still containing food-yolk, has a globular cephalothorax, and a long
segmented abdomen ending in a large fan-shaped tail. All the appendages are
represented, including those of the abdomen: these latter are similar in form to
those of the adult, the last pair (swimmerets) being concealed beneath the termi-
nal fan.

2. On Some Curious Habits of Land Hermit-crabs.

      (a ) Birgus latro. —The uninhabited island of S. Sentinel, which lies about 15
miles to the north-west of Little Andaman I., is the only place known to me, in the
seas of India, where the Robber-crab (Birgus latro) is found. It may possibly
have once had a wider range in these islands and may have been exterminated
elsewhere; either by man or by the Andaman pig; and its survival on South Senti-
el may, possibly, be due to the fact that the island stands wellout in unsheltered
water, beyond the influence of the Andamanese and of Sus andamanicus.

      In April, 1899, these great crabs were numerous in the jungle, which on South.
Sentinel is remarkably open and accessible: they were found among the spread-
ing roots of the large trees and under fallen trunks, " by companies," the males
being much more numerous than the females. During the heat of the day they
were lethargic and kept cover, but when late in the afternoon a shower of rain fell;
they became active. Individuals kept alive on board the " Investigator"
remained hidden during the day, but were very active at night, when also any that
died were eaten by their fellows. I observed one of these crabs drinking from a
runnel of rain-water, by dipping the fingers of one of its chelipeds into the water
and then carrying the wet fingers to its mouth.