8 Geographical Distribution of Crustacea. 
theride, which contains eight species in the 'lorrid zone and 
fifteen in the ''emperate. Considering the genera, however, we 
find that several among the Grapside may be called cold-water 
genera, or are about equally divided between the 'lorrid and 
''emperate zones. "'Dhey are as follows: 
Torrid species. "lemp'te species. 
Pseudograpsus, . 
Heterograpsus, 
Brachynotus, 
Planes, 
Hemigrapsus, 
Cyrtograpsus, 
Chasmagnathus, 
t0 HP» ti$00rn 
ES I2 OU t2 I IR 0D 
Five out of twelve species of Grapsus also reach into the colder 
seas. Further particulars will be gathered from the tables. 
XIIL 'The Leucosoids include as cold-water genera the fol- 
lowing : 
'lorrid. '"emperate. 
Genus Ebalia, : : : ; : 0 8 
Ep diac : . : : : E 0 1 
'The other genera are mainly confined to the 'lTorrid zone; 
out of the species they contain, sixty-seven in all, forty-eight are 
of this zone. Hepatus, however, contains as many:cold-water 
as warm-water species, and the same is true of Dorippe, although 
but one of the species of the latter is exclusively ''emperate. 
XIV. 'T'he tropies afford not only a larger number of species 
of Brachyura than the temperate zone, but also a much greater 
. proportion of individuals of the several species. —Crustacean life, 
of this tribe, is far the most prolific in the warm waters of the 
globe. Species are very abundant about coral islands, far ex- 
ceeding what may be found in other regions. 
XV. 'The actual mass of Brachyura appears also to be the 
largest in the tropics, although there are genera, as Macrocheira 
and Cancer, which have their largest species in the colder waters, 
and which exceed in size any other Brachyura. 'The genera 
Atergatis, Carpilius, Xantho, Menippe, Zozymus, Eriphia, 'T'hal- 
amita, Charybdis, Calappa, besides others of the 'lorrid zone, 
contain many large species, which are of very common occur- 
rence ; while the cold-water genera of Maioids appear to be much 
less prolific in species, and the other genera, though abounding 
in individuals, as Cancer and Lupa, are still but few in number. 
Any very exact comparison, however, of the two zones in this 
particular cannot be made without more data than have yet been 
collected. 
II. ANOUMOURA. 
XVI. 'The Anoumoura are nearly equally divided between the 
torrid and temperate zones, there being hardly one-tenth more 
torrid than cold-water species. Only fifteen species out of two 
