ORNITHOLOGICAL CLUB, 
61 
distinction fails to hold. In the Vireonidw^ for instance, species of 
thc-^ame genus have indifferently “nine” or “ten” primaries. 
Thus, Vireo philadelphicus and V, gihus are two species so much 
alike that presence or absence of a spurious “ first ” primary be- 
comes the readiest means of distinguishing them. Noting this 
remarkable circumstance in 1865, Professor Baird was led to look 
more closely into the matter. His results are summed on page 325 
of the “Review of American Birds” (see also p. 160); from which 
it appears that in those Vireos which seem to have only nine prima- 
ries, two little feathers, distinct in size, shape, and to some extent in 
position from< the general series of primary coverts, are found at the 
base of the supposed first primary ; while in those Vireos with an ob- 
vious spurious first primary, making ten in all, only one such feather 
is found. “ In all the families of Passeres where the existence of 
nine primaries is supposed to be characteristic,” he continues, “ I 
have invariably found, as far as my examinations have extended, 
that there were two of the small feathers referred to, while in those 
of ten primaries but one could be detected.” He does not specify 
how far his examinations extended. 
Believing this to be an important matter, which would bear fur- 
ther investigation, I have been led to look into the question, with 
the most satisfactory results, confirming Professor Baird’s observa- 
tions, and extending them to include every one of the North Ameri- 
can families of Oscines^ excepting, perhaps, Laniidoe (in Gollurio) and 
Ampelidoe (in Ampelis). With the possible exception of the two 
genera specified, I find, on examining numerous genera of all the 
North American families, that those rated as 10-primaried have but 
one of these little feathers, while all the rest have two. 
The Alaudidoe, like the Vireonidoe^ show a variability of the 
primaries. In our genus Eremophila, in which only nine primaries 
are developed, there are two of the small feathers above mentioned. 
The overlying one is exactly like one of the primary coverts ; the 
other, though not very dissimilar, more resembles an abortive 
primary. In Alauda arveiisis, where there is a minute but obvious 
spurious quill, there is but one such feather. In Galerita cristata, 
with a spurious quill about two thirds of an inch long, there is like- 
wise but one. 
In clamatorial .Passeres, perhaps without exception, there are ten 
fully developed primaries, the first of which may equal or exceed the 
next in length. In the single North American clamatorial family 
