386 
This is an interesting and important acquisition, and may at 
last enable us to determine with certainty a disputed point in our 
ornithology, and to remove whatever confusion still remains. 
There are three varieties of North American hawks, each of 
. which is probably a distinct species, in regard to which some 
eonfusion has prevailed. These are the common Red-tailed 
Hawk of the Atlantic States, (Buteo borealis,) B. Swainsoni, and 
the California Red-tail, described by Nuttall as B. montanus. 
The last has only recently been admitted to be a good species. 
In regard to all three there has been some difficulty in determin- 
ing their specific distinctions, and they have been more or less 
confounded by writers. Mr. Audubon gives for the B. Swainsont 
a figure of the Red-tail, and Mr. Cassin, in his Synopsis of the 
Birds of Prey accompanying his illustrated work, confounds the 
Western Red-tail with Swainson’s Buzzard. Soon after its 
publication, having an opportunity to examine three genuine 
specimens of the latter, he is convinced of their distinctness, and 
that he had till then never seen a genuine B. Swainsont. 1n 
the same paper, however, Mr. Cassin expresses the belief that 
there is no specific difference between the eastern and western 
Red-tailed Hawks. This opinion, however, he has since recalled. 
His attention having been called to differences in their eggs, in 
the cries of the bird, and finding also constant differences in their 
plumage, he has since admitted the Western bird to be a distinet 
species, to which Mr. Nuttall’s name of Buteo montanus belongs 
Mr. Samuels’s specimens of ‘the birds and eggs will, without 
doubt, afford satisfactory evidence of the correctness of these 
conclusions, and determine this interesting question beyond 
further doubt. 
: Dr. Kneeland presented, in the name of Dr. James C. 
Parkinson, of Bridgeboro', New Jersey, descriptions of 
two new Argonauts, A. Conradi, and A. fragilis. 
A. Conradi.— Oblong ovate, surface minutely granulated, a 
- the granulations being chiefly in the grooves between the ribs, Tor 
and on the tubercles: very few on the ribs. Sides convex : 
. toward the carina, plane toward the lip. Ribs rather S% > 
oe rm the umbo: broad, elevated, except anteriorly, where 
