KALCONID^ — THE FALCONS. 213 



stron.cly cnrvod, very nrutu. Wings very loiifr, the thiri' or Ibiirtli quills loiifrest ; first 

 shorter tlmii the sixth; outer three to live with inner webs sinuateil. Tail very long, 

 alioiif two thirds the wiiiL'; rounili!(i. 



The relatiniiships oi' tliis wcU-niarked genus arc, to Arnpifir on the on(> 

 hand, and Elanu.t (in the other; nearest tlie I'ornier, tliough it is not verv in- 

 timately allied to either. 1 cannot tidniit the sid)genera proposed l)y viU'iotis 

 authors (see synonomy above), as I consider the chiiracters upon which they 

 are based to be merely of specific importance, scarcely two species being 

 exactly alike in the minute details of their form. 



Tlie species are ([uite numerous, numbering about twenty, of wliicli only 

 about four (including the climatic sub-species, or geographical races) are 

 American. North America possesses but one (C. liudsonim, I.inn.), and this, 

 with the C. cincreus, Vieill, of South America, I consider to be a geo- 

 grai)hical race of C. cyanms of Europe. 



The birds of this genus frequent open, generally marshy, localities, where 

 they course over the meadows, moors, or marslies, witli a steady, gliding 

 flight, seldom flapping, in pursuit of their food, which consists mainly of 

 mice, small birds, and reptiles. Tlieir assault upon the latter is sudden and 

 determined, like the " Swift Hawks," or the species of Arcipifcr. 



In the following synopsis, I include only the three forms of C. cj/ancvs, 

 giving the characters of the European race along with those of the two 

 American ones. 



Species and Baces. 



C. cyaneuB. Wing, 12.50 -IG.OO; tail, 9.00-10.70; pulmen, .00 -.80; 

 tar.sus, 2.42 - 3.25 ; middle too, 1.10-1.55. Third to fourth quills longe.st ; 

 first shorter than sixth or seventh ; outer four with inner webs sinuated. 

 Adult male} Above pearly-ash, with a bluish cast in some parts ; breast 

 similar; beneath white, with or without rufous markings. Adult female. 

 Above brown, variegated with ochraccous on the scapuhws and wing- 

 coverts; beneath yellowish-white or pale ochraccous, with a few longitudi- 

 nal stripes of brcvvn. Younrf (of both sexes). Like the adult female, but 

 darker brown above, the spotting deeper ochraccous, or rufous ; beneath 

 pale rufous, the stripes less distinct. 



Tail and secondaries without a subterminal band of du.sky ; lower 

 parts without any markings. 



AVing, 12.50 - 15.00 ; tail, 9.00 - 10.70 ; culmen, .GO -.75; tarsus, 

 2.70 -2.85; middle toe, 1.10-1.35. Hah. Europe . \a.\: cy an eus:^ 



1 The females and immature males are hard to distinguish, and from the unsatisfactory tliiiriic- 

 ter of the material at my eomnmnd I have not .succeeded in finding reliable charaiti'is by which 

 these i)lumages of the three races may he distingni,shed. Coiiseipieutly I give only the characters 

 of the adult males, in defining the distinctions between them. 



' Circus q/aneiis, var. ci/imcus (Linn.). Fahv cijaneua, Linn. S. N. 1766, 126. Circus cija- 

 HCKS, Less. Man. Orn. I, 105. — Odri.D, B. Europe, pi. xxxiii. — BoxAr. List, 22. — Deol. 

 Orn. Eur. I, 74. — Stkicki,. Orn. Syn. I, 147. — Gray, Hand List, I, 37, No. 364. Falco 

 pygargm, Linn. S. N. 1766, 126. Circus pygargus. 8ri-.ru. Zool. XIII, pi. ii, 41. 



Specimens examined. — National Museum, 3 ; Philadelphia Academy, 4 ; New York Museum, 

 1 ; Boston Society, 6. Total, 13. 



