o76 PROCEEDINGS OF THE ACADEMY OP 



through fuscescens and Holbollii, is gradual, we see not the slightest cause for 

 separating it, even sub-generically. Moreover, if distinctions were founded 

 upon size of bill, there is no reason why a similar discrepancy in the size and 

 proportions of the feet should not be made the grounds of division, and thus 

 it would be necessary to separate the A. canescens and exilipes ; a procedure 

 hardly warrantable. We think it probable that the genus, as far as can be 

 judged from the species now known to compose it, is incapable of a natural 

 division. 



Throughout this genus the most tangible evidence of immaturity, next to 

 the absence of the rosy tints on the breast and rump, lies in the presence of a 

 general yellowish or rufous suffusion, particularly about the head and fore- 

 parts of the body. This is accompanied by a general indistinctness of outline 

 of the streaks, the dusky being bordered with reddish, which fades insensibly 

 into the white ground color. Indeed, we are of opinion that this rule is capa- 

 ble of much more extensive application, embracing perhaps the greater part 

 of the genera of the Fringillidce the species of which are streaked. It is very 

 evident in young specimens of Passerculus savanna, Poecetes gramineus, Melo- 

 spiza melodia, and other allied species, and in some species of Plectrophanes, the 

 females of which resemble the streaked sparrows very closely. Moreover, iu 

 some species, as for example, the Spizella socialis and Coturniculus passerinus, the 

 presence of streaks below is an evidence of immaturity, these streaks entirely 

 disappearing when the bird is fully adult. 



The "theory of variation," then, in this genus, so far as regards the plumage, 

 would seem to be essentially the same as that which is most usual throughout 

 the family, though agreeing most closely with that exhibited by the Spizel- 

 linaz (of Baird, as denned by that author). The sexual variations, however, in 

 the absence in the female, of the red which is the most conspicuous color of 

 the male, is precisely the same as is seen in allied coccothraustine types, such 

 as Pinicola, Carpodacits, Curvirostra, etc. 



Geographical Distribution. The genus i3 entirely confined to the Northern 

 hemisphere, being unknown in Africa or South America. It is, moreover, em- 

 phatically a boreal genus, all the species inhabiting high latitudes, and only 

 coming south during the winter. The species, as far as now known, are very 

 equally distributed. One is common to Europe and America; two are peculiar 

 to America ; two to Europe ; and two inhabit the neutral ground of Greenland. 

 Both the latter, however, are probably found at times in Europe, and may also 

 very possibly be detected on our own continent. 



Comparison with allied Genera. The genus is most closely allied to Canna- 

 bina, a European form, with Fringilla cannabina Linn., as type, both having 

 much the same general form and appearance. The differences, however, are 

 readily appreciable, and quite sufficient to separate the two. In Linota the bill 

 is much larger, stouter and more turgid, and less compressed and acute, and 

 the nasal plumuli are very much shorter. The feet are larger and stronger, the 

 toes especially much longer, the middle one, without the claw, being nearly as 

 long as the tarsus. The hind toe is as long as its claw. The tail is shorter, 

 less forked, its feathers much narrower and more acute. The wings are much 

 the same. The general pattern of coloration is the same; but the colors of the 

 back are in well defined areas ; the throat is streaked ; the tail and wings with 

 very broad well defined white edges, etc. Apparently the most essential dis- 

 tinctive characters are those lying in the feet. Leucosticte is the most closely 

 allied North American genus, agreeing with JEgiotlms in many respects. It 

 differs, however, in a stouter, more turgid, less compressed and acute bill, with 

 its decidedly convex culmen ; in the presence of ridges on the lower mandible. 

 The tail is much less forked, and the feathers are even broader, with more ob- 

 tuse tips. The feet are much the same; but the lateral toes, in comparison 

 with the middle, are shorter. The claws are shorter. Chrysomilris, with Frin- 

 gilla spinus L., as type, has even a more compressed, attenuated and acute bill, 

 but the culmen is much curved ; the nasal plumuli are exceedingly short; the 



[Nov. 



