Geographical Distribution Y Crustacea. —J 
the warm East Indies (at the Moluccas), as De Haan states, four 
dn neri 1s the greatest length. j 
IIl. MACROURA. 
. (The Macroura, according to the table, [see Report,] are 
equally divided between the torrid and ex ra-torrid zones, - 
. the ormer including one hundred and forty- -seven species, and 
! the lat er one hundred aud fifty-three species. 
the table we have not included the fresh-water POUHcc 
as we are treating only of marine species. Yet in a compari- 
son of numbers between the zones, these should be brought in. 
"They are about thirty-six 1n number, aud all, excepting perhaps 
one, belong to the temperate zone as regards the temperature of 
the waters they frequent. With this addition, the numbers be- 
come 147 for the torrid zone, and 189 for the extra-torrid. Sixteen 
of the cold-water species are common to both the torrid aud tem- 
perate zones, and twenty-nine occur in the frizid zone, twenty- 
seven being peculiar to this zone. This is strikingly in contrast 
with the Brachyura, of which two-thirds are torrid species, and 
only five or six are known to extend into the cold zone, of which: 
but one as far is known, is confined to 1t. 
XX. 'l'he Thalassinidea are mainly extra-torrid species. 
'The Astacidea are divided between the warm and cold seas; 
the Palinuride and Scyllaridae being mostly of the former, aud 
the Astacid& almost exclusively of the latter. 
"The Caridea spread largely over both zones; but extensive 
groups are extra-torrid, and some genera contain many frigid 
species. 
'The Penaeidea are mainly of the torrid zone. 
'The exact ratios may be gathered from the tables. 
XXL. 'The geographical relations of the subordinate groups 
are shown in the following table. 
l. TEMPERATE AND FRIGID ZONE SECTION. 
. Species in'the — Species in the Temper- 
''orrid zone. ate and Frigid zones, 
Thalassinidea, , : : MM T 1" 
Astacidea, : : : ; 24 50 
Astacid:e, : ond 46 
Scyllaridie, G. Arctus, : 0 MT 
Palinuride, G. Polinurus, i 312 8 
Caridea. 
Crangonidze, : 2 25 
Atyide, G. Ephyra, . 0 2 
Palemonids. 
Alpheinze, G. Betcus, 1 4 
Álope, 0 b 
AAthanas, 0 1 
Hippolyte, 8 3'I (19 frigid). 
Pandaline, G. Pendalus, 0 4 (2 frigid). 
Palemonins, G. Cryphiops, 0 1.54 
Pasiphzidse, G. Wappen. 0 8 (1 frigid). 
Pensidea, G. Eucopia, 0 1 (frigid). 
