VIREO. 197 
sometimes over the whole surface, but oftener chiefly at the larger end’. Brewer 
describes its song as peculiar, being a frequent repetition of the same notes. 
Regarding the bird from Coban, in Guatemala, described by Prof. Baird as Vireo- 
sylvia propingua °, we are in some doubt as to its position, as we have never seen a 
second specimen presenting the same differences from Vireo solitarius that Prof. Baird’s 
type does, which we have again before us for examination. These differences are as 
follows :—The grey of the head is more restricted, the olive colour of the back extending 
over the nape and to behind the ears; the upper tail-coverts are ashy instead of olive; 
the sides of the throat are yellow instead of white; the flanks are white tinged with 
olive, not olive-green tinged with yellow; the anal region is white, not yellow; the 
spurious primary is much smaller, and the second quill longer instead of shorter than 
the fifth ; the wing is slightly longer, and the bill broader at the base. These are the 
differences pointed out by Prof. Baird; and we find that they are all as he describes 
them. They are all small individually, but taken together are certainly remarkable ; 
and it is noteworthy that they nearly all are slight divergences from the typical 
V. solitarius in the direction of V. flavifrons! Have we here the remains of some cross 
between these two birds? The type of V. propinguus was obtained with numbers of 
the true V. solitarius and V. flavifrons at their winter quarters near Coban; and the 
discrepancies from JV. solitarius were not noticed at the time, nor, indeed, till Prof. 
Baird pointed them out. ‘hata resident local race of V. solitarius exists in Guate- 
mala !° we hesitate to believe until further evidence can be produced; and in the mean- 
time we leave V. propinquus in an uncertain position, with the above suggestion as to 
its origin. 
11. Vireo cassini. 
Vireo cassini, Xantus, Pr. Ac. Phil. 1858, p. 117’. 
Lanivireo solitarius, var. cassini, Baird, Brew. & Ridgw. N. Am. B. i. p. 376’. 
Vireo solitarius cassint, Coues, B. Col. Vall. i. p. 514°. 
Vireosylvia solitaria, Salv. Cat. Strick]. Col. p. 112* (partim). 
V. solitarzo similis, sed pileo cinereo olivaceo tincto fere dorso concolori et pectore pallide fulvo perfuso vix 
distinguendus. (Descr. exempl. ex Mexico. Mus. Ac. Cantabr.) 
Hab. Norru America, California !?, Nevada, Arizona *.—Mexico (Galeotti *). 
A single skin in the Strickland collection, sent from Mexico by Galeotti in 1845, we 
recognize as belonging to this race, as it agrees with authentic specimens from Calaveras 
county, California, recently forwarded to us by Mr. Ridgway. The bird would appear 
to be not uncommon in the Gila valley, where Mr. Henshaw met with it at the end of 
August and in September, in company with but rarer than JV. solitarius, the only 
difference in the habits of the two birds being the preference of the former for 
deciduous trees, the latter choosing the coniferous timber®. The appearance of these 
