FOREST, AND ITS FAUNA 49 
both the Siberian and Canadian taiga they form a very 
large part of the natural food of the pine grosbeak — 
(Pinicola enucleator), a gorgeous bird related to the 
bullfinch, and of the crossbill (Loxia curvirostra), also 
with bright-coloured plumage. Pine cones, it will be 
remembered, ripen slowly, and during the ripening 
process the seeds are carefully protected by the closing 
of the scales, so that their extrication is a matter of 
difficulty. The forester is constrained to apply heat to 
obtain the seeds without damage, but the crossbills 
have the beak converted into an instrument by means 
of which the seeds are readily prized out. More slashing 
are the methods of the nutcracker (Nucifraga caryo- 
catactes), which in the Alps, as in Siberia, may be seen 
breaking the cones of the Cembra pine to pieces with 
its powerful bill. The western coniferous wood of 
North America is inhabited by another species. Re- 
lated to the nutcrackers are the magpies and jays, the 
latter represented in the eastern taiga by the Siberian 
jay (Perisoreus infaustus), with soft fluffy plumage of 
a reddish colour. 
Reptiles and amphibians are few in number in the 
northern forest, the former especially. Among am- 
phibia, frogs and toads haunt the pools and swamps, 
an important form being the large bull-frog (Rana 
catesbiana) of North America, which is exceedingly 
voracious, devouring fish, young. water-birds, &c., and 
derives its common name from its noisy croak, which is 
compared to the roaring of a bull. The tree-frogs 
(Hylidae), with their usually greenish colour and the 
curious adhesive pads at the ends of the toes, by means 
of which they keep their foothold, have a much wider 
distribution in America than in the Old World. In 
the Eurasiatic continent the common tree-frog (Hyla 
1404 D 
