154 
Lawrence on the Greater Long-Beak. 
is still within the equatorial belt. Our Orioles, Tanagers, Grackles, 
Hummingbirds, and Vultures, for example, are really but stragglers 
or outlying species of groups that are mainly tropical. Even the 
great family of Wood-warblers ( Mniotiltidoe ) has species, indeed 
whole genera, that are still confined within tropical limits, including 
even species of that most characteristic North American genus 
Dendroeca. Even at the present time, the birds which breed in 
tropical regions are, as a rule, sedentary, this being true also of 
species which belong to wide-ranging genera, the representatives of 
which, found in extra- tropical districts, are migratory. It may be 
fairly inferred that the characteristic groups of the lower latitudes 
have originated within the areas of their present distribution, and 
that their normal condition is that of sedentary birds. In the outly- 
ing species of such groups, which visit high latitudes to breed, the 
instinct of migration may be supposed to have been of gradual de- 
velopment, induced by the struggle for existence and the climatal 
changes that have' rendered migration advantageous. The fact of 
many species being in part migratory and in part sedentary, in ac- 
cordance with the breeding station of the individual, seems to point, 
not only to the gradual extension of such species from warm to 
colder districts, as indicated by other considerations, but to the 
comparatively recent origin of the instinct of migration, in virtue of 
the causes and in the manner already detailed. 
THE GREATER LONG-BEAK, MACRORHAMPHUS SCOLO- 
, PACE US (SAY). 
BY NEWBOLD T. LAWRENCE. 
As this bird seems to be held by certain eminent ornithologists 
to be rather a doubtful species or even variety, I should like to give 
my experience with it on the south side of Long Island, where I have 
had the pleasure of securing four specimens and noting two others, 
and also give the result of the examination of some forty specimens 
of both birds. Dr. Elliott Coues says : “ The supposed species 
(M. scolopaceus ), based on larger size and larger bill, is not even 
entitled to rank as a variety. Almost any flock contains a per cent 
of such individuals. The difference in these respects is merely the 
