Hoplocarida — Stomatopoda. 
47 
to the common Gammarus, found in Lake Baikal ; and that the Table-case 
little Chelura terebrans is, of all Amphipoda, perhaps the most No - 7 - 
directly important to man on account of its destructiveness to 
marine timber referred to above (p. 42). 
The members of the Sub-order Hypebiidea can generally be 
recognised by the very large eyes, which may cover almost the 
whole surface of the head. The first thoracic limbs (maxillipeds) 
are reduced. Most of the species are pelagic in habit, living at the 
surface of the open sea. One of the most remarkable is Phronima 
sedentaria which lives on various pelagic organisms, like jelly- 
fishes and salps, and often carries about with it as a kind of cloak 
the remains of its prey. One of the two specimens here shown is 
enclosed in a barrel-shaped case, the remains of a swimming-bell 
of one of the Siphonophoran jelly-fishes. 
In the Sub-order Capbellidea the body is either slender and 
thread-like (Caprellidae), or broad and flattened (Cyamidae). The 
abdomen and its limbs are vestigial. 
The Caprellidae (Fig. 28) are generally found among Zoophytes 
or seaweeds. A group of specimens mounted in natural sur- 
roundings is shown in Wall-case No. 4. 
The Cyamidae , or “ Whale-Lice,” are parasitic on Whales, and 
are sometimes found in large numbers clinging to their skin. 
Division 4. — HOPLOCARIDA. 
Four or five of the posterior thoracic somites are free Table-case 
from the carapace. There is no brood-pouch. Two movable No ' 8 ‘ 
segments are separated from the anterior part of the head, 
bearing respectively the pedunculate eyes and the antennules, 
and there is a movable rostral plate in front of the carapace. 
The first five pairs of thoracic limbs are subchelate, and the 
second pair are very large. The last three pairs carry exopodites. 
There are tufted gills borne by the first five pairs of abdominal 
appendages. 
This division includes the single order Stomatopoda, the 
members of which are abundant in the warmer seas. They are 
generally easily recognised by the characteristic form of the large 
claws, which are not pincer-shaped, like those of Lobsters and 
Crabs, but have the last segment shutting down, like a knife-blade, 
on the segment before it. 
One species of Squilla ( S . desmarestii ) occurs occasionally 
