220 
ZOOLOGICAL LITERATURE. 
the similarity of the Cape Verde islands to the Canaries and 
Madeiras (combined) is greater than that between the two 
latter archipelagos ; and the whole evidence points overwhelm- 
ingly, as Wollaston remarks, to the conclusion that these islands 
are the outposts of a single gigantic province which has been 
rent asunder, and is now principally submerged.^^ 
Crotch, in his memoir on the Azorean Coleoptera (Proc. Zool. 
Soc. 1867, pp. 359-391), enumerates in all 213 species of Bee- 
tles as known to occur in those islands; but of these 12 are 
cosmopolitan forms, reducing the number to 201. Of these 
only 30 are regarded by the author as belonging to the Atlantic 
fauna, thus leaving 171 European species. The great propor- 
tion of these to the whole may undoubtedly be due, as Crotch 
suggests, to the fact that the collections have been made for the 
most part in the lower and more cultivated districts, and that 
an investigation of the districts more remote from the coasts 
and the towns would furnish a larger number of Atlantic forms ; 
but the results of the present investigations seem to show that 
the European species will probably always bear a larger propor- 
tion to the Atlantic ones than in the more southern groups. 
But of the 171 European speeies enumerated. Crotch believes 
that only 70 are truly indigenous, the remaining 101 having 
probably been introduced by colonists. 
In comparing the Coleopterous fauna of the Azores with those 
of the Madeiras and the Canaries, Crotch finds the closest rela- 
tionship with the former group of islands. The Azores and 
Madeira have 1 lO species in common ; but of these, 123 occur 
also in Europe, out of which 97 likewise inhabit the Canaries. 
Only 8 are peeuliar to the Azores and Madeira, and 8 more are 
common to these islands and the Canaries ; these constitute 
the truly Atlantie species, among which a Paramecosomaj an 
Homalium, and a Phlceophagus are regarded by the author as 
autochthonous.” 
The Azores and Canaries have 114 species in common, only 
2 of which are peculiar to the two groups of islands. Two 
species are common to the Azores and the Salvages ; 3 species, 
namely, jEoIus melliculuSj Monocrepidius posticus, and Tesniotes 
scalaris, oceur in Ameriea ; ^nd a fourth, Hctcrodcrcs azoricas, 
is probably derived by modification from an American species. 
Staphylinus hespei'us (a new species) has a close ally at the 
Cape of Good Hope, and Elastrus dolosus finds its congeners 
only in Madagascar, and in external form closely resembles 
some Elaters from the Cape of Good Hope. 
The proportions of the families, as compared with those oc- 
curring in the Madeiras and Canaries, are shown by Crotch in 
the following table : — 
