328 BULLETIN OF THE 



carefully examining the birds described above, I do not see, if Buteo bo- 

 rea/is, monlanus, and calurus are to be considered distinct species, that we 

 can avoid increasing the number by separating from montanus two species, 

 — one the dark Stcilacoom variety, and the other that from Cape St. 

 Lucas (which, by the way, is the most distinct variety that I have seen) ; 

 from calurus, one species, the ferruginous variety from Fort Tejon; and 

 adding to this group one species based on the adult Harlani of the Acad- 

 emy \_Harlani of Cassin, not of Audubon], making in all seven species 

 of this group. I have not included in this list the youiig Harlani of the 

 Academy, which differs as much from the adult as from any other speci- 

 men of this group ; or Cooperi" etc. After next describing in detail 

 Buteo Harlani (B. Harlani of Bryant, not B. Harlani of Cassin, nor of 

 Audubon), and its several varieties, which form the " species" B. insigna- 

 tus, Sioainsoni, and oxypterus of Cassin and the B. Bairdii of Hoy and 

 Cassin, with several varieties under each, some of which lie clearly shows 

 are connecting links to others, Dr. Bryant concludes his paper with the 

 following summary : " Taking color, therefore as a sufficient ground for 

 specific distinction, we find that we have in the red-tailed group seven 

 species, and in the other nine, which, with the young Harlani of the 

 Academy, Cooperi, fuliijinosus, albonolatus, lineatus, elegans, and pennsyl- 

 vanicus, give a total of twenty-three species of this genus which are found 

 in the United States." 



But Dr. Bryant by no means admits color in this group to be a specific 

 characteristic, and, as I have already remarked, in reducing the number 

 of species of the red-tailed hawks to two, he takes general size and the 

 proportions of the primary quills of the wing as the basis of distinction. 

 He has accordingly given a table of comparative measurements and pro- 

 portions of the two species, in which he has arranged, as he says and 

 doubtless supposed, the larger specimens under B. borealis, and the smaller 

 under B. Harlani. Size and the proportions of the quills, however, it 

 seems to me, arc equally ai-bitrary grounds for their separation, as an 

 examination of his tables and descriptions evidently proves. It hap- 

 pens that in the first, or B. borealis series, marly all the specimens 

 are fully adult, as indicated by the tail being uniformly red, with a subter- 

 minal black band, — a stage of plumage which characterizes only adult 

 individuals. In the second, or B. Harlani series, but one specimen (which 

 does not appear in the table of measurements), is described that is not 

 evidently somewhat immature, while the greater part of them are quite 

 so.* Respecting the so-called Buteo Bairdii, of which numerous speci- 

 mens have been reported, some from quite eastern localities, Dr. Bryant 



* They have at least the tail numerously banded, a6 all immature B. borealis do have, 

 and their general diagnosis is that of immature birds. 



