La:MODIPODA. 429 
the order Isopoda), namely, the Crevettines and the Hyperines, the former divided into the saltatorial 1 
and ambulatory species. Some new genera were added, especially in the singular family of the Hyperines. 
Pterygocera, Latr., and some other genera, he considers not sufficiently studied, and consequently of 
doubtful character and situation. Apseudes, lone, Anceus, and Praniza, he also regards as isojiodous. 
Various additional genera have also been established by M. Guerin de Meneville, in the Magasiu de 
Zoologie, especially amongst the Hyperines, and which are accompanied by figures and generic details. 
Dr. Templeton has described some curious minute species from Mauritius, in the Transactions of the 
Entomological Society. Still more recently I have received from M. Kroyer, the Danish naturalist, a 
memoir upon the Amphipoda of Greenland, published in the last part of the Copenhagen Transactions. 
Rathke has described many new species, and some new genera from the Caspian Sea, in the last volume 
of the Petersburg Memoirs, and Professor Owen has described some interesting species brought home in 
one of the late Polar expeditions. One of the most remarkable of the subgenera established, is that of 
Orio of A. Cocco, described in the Giornali di Scienze, ^c., per la Sicilia, for November 1 833, which has 
been overlooked by Crustaceologists, and in which the maxillary palpi are exceedingly slender, as long 
as the body, and 4-jointed.] 
THE FOURTH ORDER OF CRUSTACEA, 
LCEMODIPODA,— 
Comprises the only Malacostraca with sessile eyes which have not distinct branchim attached 
at the extremity of the body, which are nearly destitute of a tail, the hind pair of legs being 
attached either at the extremity of the body or to a segment, follow^ed by one or two very 
small joints. They are also the only species in which the two fore-legs, which correspond 
with the second foot-jaws, form part of the head. 
All the species have four setaceous antennae, implanted on a peduncle of three joints ; 
mandibles destitute of palpi ; a vesicular body at the base of at least four of the pairs of legs, 
commencing with the second or third pair, including those of the head. The body, generally 
[ filiform or linear, is composed (including the head) of eight or nine segments, with several 
i small appendages in the form of tubercles at its posterior and inferior extremity. The legs 
1 are terminated by a strong hook ; the four anterior, of which the second pair is the largest, are 
always terminated by a monodactyle claw\ In some, the four following are more slender, 
with fewer articulations, without a terminal hook, or are rudimental ami in no manner fitted 
for the ordinary uses. 
The females carry their eggs beneath the second and third segments of the body, in a pouch 
1 formed of scales closely applied against each other. 
All these Crustacea are marine. M. Savigny considers them as approaching the Pycno- 
j gonides, and as forming, together with them, the passage betw^een the Crustacea and 
I Arachmda. In the first edition of this work, they formed part of the Isopodous order, namely, 
1 the section Cystibranchiae. 
I They may be considered as forming a single genus, for which, on account of its priority, the name of 
! Cyamus (Latr.) — 
should be retained. 
Some of these (forming a first section named Filiformia, Latr.) have the body long and very slender 
or linear, with the segments longitudinal ; the legs also long and very slender, and the terminal fila- 
ment of the antennse composed of minute joints. 
They are found amongst marine plants, creeping along in the same way as the Geometer or Looper- 
caterpillars, bending themselves often back with great rapidity, and applying their antennae to various 
parts of the body. In swimming they bend the two ends of the body dowiiw^ards. 
