404 
GALAPAGOS ARCHIPELAGO 
CHAP. 
been subjected. Although no one has a right to speculate 
without distinct facts, yet even with respect to the Chatham 
Island mouse, it should be borne in mind that it may possibly 
be an American species imported here ; for I have seen, in a 
most unfrequented part of the Pampas, a native mouse living 
in the roof of a newly-built hovel, and therefore its transportation 
in a vessel is not improbable: analogous facts have been 
observed by Dr. Richardson in North America. 
Of land-birds I obtained twenty-six kinds, all peculiar to 
the group and found nowhere else, with the exception of one 
lark-like finch from North America (Dolichonyx oryzivorus), 
which ranges on that continent as far north as 54 0 , and generally 
frequents marshes. The other twenty-five birds consist, firstly, 
of a hawk, curiously intermediate in structure between a 
Buzzard and the American group of carrion-feeding Polybori ; 
and with these latter birds it agrees most closely in every 
habit and even tone of voice. Secondly, there are two owls, 
representing the short-eared and white barn-owls of Europe. 
Thirdly, a wren, three tyrant-flycatchers (two of them species 
of Pyrocephalus, one or both of which would be ranked by 
some ornithologists as only varieties), and a dove—all analogous 
to, but distinct from, American species. Fourthly, a swallow, 
which though differing from the Progne purpurea of both 
Americas, only in being rather duller coloured, smaller, and 
slenderer, is considered by Mr. Gould as specifically distinct. 
Fifthly, there are three species of mocking-thrush—a form 
highly characteristic of America. The remaining land-birds 
form a most singular group of finches, related to each other in 
the structure of their beaks, short tails, form of body, and 
plumage: there are thirteen species, which Mr. Gould has 
divided into four sub-groups. All these species are peculiar 
to this archipelago ; and so is the whole group, with the 
exception of one species of the sub-group Cactornis, lately 
brought from Bow Island, in the Fow Archipelago. Of 
Cactornis the two species may be often seen climbing about 
the flowers of the great cactus-trees ; but all the other species 
of this group of finches, mingled together in flocks, feed on the 
dry and sterile ground of the lower districts. The males of 
all,- or certainly of the greater number, are jet-black ; and the 
females (with perhaps one or two exceptions) are brown. The 
