228 Mr. R. W. Shufeldt on the 



Swiftlets build their nests crowded together ou the face of 

 steep and almost inaccessible cliffs, so that it is very difficult 

 and dangerous to obtain them. M. Pollen observes that in 

 the nests both eggs and young birds in all stages of develop- 

 ment may be found. One of this bird's names is Voromaola, 

 " Frolicsome-bird '^ (or possibly '' Mad-bird ^^), probably 

 from its wild dashing flight as it darts after its insect prey. 



[To be continued.] 



XXII. — Some Comparative Osteological Notes on the North- 

 American Kites. By R. W. Shufeldt, C.M.Z.S. 



Very recently the writer has been engaged in making com- 

 parisons of the characters presented in the skeletons of 

 nearly all the genera of the Accipitres found north of the 

 northern boundary of Mexico. By the Accipitres I mean 

 the Cathartidse, the Falconidse, and Pandion, but not the 

 Striges. For the most of my material I am indebted to the 

 Department of Comparative Osteology of the U.S. National 

 Museum, though my own collections are not inextensive, 

 affording as they do certain specimens not in the possession 

 of the above-named institution. 



The true Raptores, including Pandion, offer us many 

 osteological characters of good classificatory value ; but when 

 we come to consider the skeletons of the Kites of North 

 America many perplexing points confront us. 



Of these latter birds I have carefully examined and com- 

 pared the skeletons of Elanoides forficatus, Elanus leucurus, 

 and Ictiiiia mississippiensis, but up to the present time no 

 opportunity has been afforded me for studying the osteology 

 of the Everglade Kite {Rostrhamus sociabilis). Not only 

 have the skeletons of these species been intercompared, but 

 comparisons have also been made with the skeletons of many 

 raptorial birds of other countries, as well as with the osteo- 

 logical characters oi Circus a.nd Accipiter (several N. -American 

 species), of many species oi Buteo and Falco, of Urubitinga 

 anthracina and Asfnrina plogiata, of American species of 



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