REVIEWS. 366 



he does us the honor (his endorsement in such a case is an honor) 

 to recognize our Pelidaa Americana — a bird that cannot stand a 

 moment upon Mr. Allen's platform ; and in one or two other in- 

 stances — that of Graculus Floriclanus, for example, unquestiona- 

 bly a southern form of G. dilophus — he is similarly untrue to his 

 principles. 



Among" the critical discussions that we mentioned just now, is a 

 highly satisfactory elucidation of the several interesting modifica- 

 tions in size, form and color that result from climatic and other 

 physical influences upon the birds. The decrease in stature, coin- 

 cident with lowering of latitude, was perhaps already sufficiently 

 known ; but the other points needed the excellent exposition they 

 receive at Mr. Allen's hands. He shows a singular tendency to 

 increase in the size of the bill of Floridan birds. This corres- 

 ponds exactly to the remarkable elongation of the tail of many 

 southwestern forms ; and his explanation — greater activity of per- 

 ipheral circulation — is doubtless as applicable to one as to the 

 other. The third characteristic of Floridan forms is an intensity 

 of coloration, as compared with Northern broods of the same spe- 

 cies. This is well illustrated in the Quail, and several other species, 

 particularly the curious \\tt\e. Pipilo in which the white markings of 

 the wings and tail are at a minimum, though the iris, singularly 

 enough, is white instead of red. * It would be difficult to over-es- 

 timate the importance that attaches to this admirable elucidation 

 of the peculiarities that collectively distinguish the Floridan birds. 

 Interesting in itself, additional value is gained in its affording data 

 for a similar exhibit of the relationships of the birds of the Lower 

 Rio Grande and Colorado rivers. Numerous forms from these 

 regions, as well as from the peculiar Cape St. Lucas locality, can 

 be better interpreted now that we have analyzed that portion of 

 the Eastern Province lying within corresponding degrees of lat- 

 itude ; and many that have been named as positive specific forms, 

 and taken to be such, may prove merely indices of geographical 

 variation occurring in strict accordance with laws that Mr. Allen 



* Pipilo Allexi, nob. — P. erythrophthalmo similis, sed minor, alls caudaque minus 

 albo-plagiatis, et iridibus albis. This interesting " form," whicli we believe remains 

 unnamed, we have great pleasure in dedicating to our esteemed friend. 



An anonymous writer of some pleasant articles on our birds in Appleton's Journal 

 (iv, p. 258) says: ''The 'Chewink' is perhaps the most curious instance of change in 

 the color of the iris, which with the summer dress is red, and with tlie winter, white — 

 the change taking place sometimes first in one eye, and then in the other, during the 

 process of the autumn moulting." This, if so, is new to us. 



