246 A HISTORY OF RECENT CRUSTACEA 
convenience of classification, it seems hardly worth while 
for the present to separate the Tropiocaride from the 
Acanthephyride. Notostomus and Gonatondtus, two genera 
established by A. Milne-Edwards in 1881, from the West 
Indies, are both said to be near Oplophorus, and both to 
have exopodal appendages to the feet. Notostomus perlatus, 
Spence Bate (see Plate XIII.), is from the Philippines. 
Fumily 6.—Palemonide. 
The carapace is dorsally rounded and lateraily com- 
pressed, the rostrum long, laterally compressed, and gene- 
rally armed with teeth. The eyes are well developed and 
pyriform. The first antennze have the basal joint dorsally 
hollowed, with a strong spine on the outer side, and 
frequently one of the flagella branched; the second pair 
have a long and narrow foliaceous scale, its rigid outer 
margin ending in a small tooth. The mandibles have 
molar tubercle and cutting edge, and either have or have 
not a ‘palp. The third maxillipeds are pediform. 
The family includes about half a dozen genera, two of 
which are found in British waters. 
Palemon, Fabricius, 1798, has been subdivided since 
its institution, and Stimpson in 1860 rightly recognised 
that Pulemon carcinus, the first in the list of species 
assigned to the genus by Fabricius, should be the type. 
Hence the genus bithynis of Philippi, to which this and 
other fresh water species have been referred, is a mere 
synonym of Palemon. The marine species, which have 
been commonly retained under the name Palemon are 
referred by Stimpson to Desmarest’s genus Leander with a 
fresh definition. 
Spence Bate gives a synopsis of the genera into which 
the original Palcemon of Fabricius has been divided, which, 
with the necessary modifications, may be thus set out :— 
Palemon, Fabricius, 1798, has one tooth on the frontal 
margin of the carapace, and a second on the 
hepatic region nearly in the same horizontal line; 
the second trunk-legs with the wrist long. 
Teander, Desmarest, 1849, has the frontal margin of 
