Geographical Distribution of Crustacea. 323 
the warm East Indies (at the Moluccas), as De Haan states, four 
inches is the greatest length. 
Ill. MACROURA. 
XIX. The Macroura, according to the table, [see Report,] are 
nearly equally divided between the torrid and extra-torrid zones, 
the former including one hundred and forty-seven species, aud 
the latter one hundred and fifty-three species. 
In the table we have not included the fresh-water Astacida, 
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 in number, and 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 frivid zone, twenty- 
seven being peculiar to this zone. his 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 it. 
- The Thalassinidea are mainly extra-torrid species. 
The Astacidea are divided between the warm and cold seas; 
the Palinuride: and Seyllaride being mostly of the former, and 
the Astacide almost exclusively of the latter.” 
he Caridea spread largely over both zones} but extensive 
groups are extra-torrid, and some genera contain many frigid 
species. 
The Penzidea are mainly of the torrid zone. 
The exact ratios may be gathered from the tables. 
XXI. The geographical relations of the subordinate groups 
ate shown in the following table. - 
: 1, TEMPERATE AND FRIGID ZONE SECTION. 
ee inthe Species inthe Temper- 
orrid zone. ate and Frigid zones. 
Thalassinidea, 6 17 
Astacidea, : : 24 50 
stacide, - é 1 46 
Scyllaride, G. Arctus, 0 1 
Palinuride, G. Palinurus, 2 3 
Crangonide, ¢ : 2 25 
Atyide, G. Ephyra, . Pee ag 
Palzemonide, cee ina 
Alpheinz, G. Beteus, > ; ; 
Alope, sia : A; 
Athanas, 0 1 oe 
Hippoliyte, 8 37 (19 frigid). 
Pandaline, G. 5 i : : : (2 frigid). 
Palemonine, G. Cryphiops, tie 
Pasiphei G. Pasiphea, . 0 3 (1 frigid). 
Penwidea, G. Zucopia, ; 0 1 (frigid). 
