186 



SIXTH RJiPORT— 1836. 



for an excellent comparison of the birds inhabiting the middle 

 parallels of the two zoological provinces. 



The following table, which exhibits to an approximate fraction 

 the proportion that each group of birds bears to the whole of 

 the known North American species, will require correction as 

 our knowledge of the ornithology of Mexico and the northern 

 shores of the Pacific imnroves. 



Groups. 



Rapaces 



VulturidEe 



FalconidDB 



Strigidse 



Insessoues 



Dentirustres 



Lauiadse 



Merulidse 



Sylviadse 



Ampelidse 



Muscicapidse . . . . 

 Conirostres 



Fringiliidce .... 



Corvidas 



iSturnida:; 



Scansores 



Picidse 



Ptfittacidse 



Ramphastidae. . . . 



CucuHda; 



Certhiadre 



Tenuirostres. Trochil. 



Grou'is. 



No. of 



sp. 



Fissirostres . . . 



Halcyonidse . 



Hirundinidae . 



Caprimulgidse 



Trogonidse. . . 

 Rasoees 



Cracidae 



Columbidse . 



Phasianidse . 



Tetraonidas . 

 Grallatores . 



Tantalidae ... 



Ardeidae 



Scolopacidae . 



Rallidae 



Charadriadje . , 

 Natatores ... 



Anatidis 



Colymbidae . 



Alcadae 



Pelecanidae . 



LaridcC 



23 



1 



9 



4 



9 



33 



3 



12 



1 



17 



87 



6 



16 



45 



9 



11 



122 



41 



8 



15 



14 



44 



Prop, 

 fr. 



To 

 i_ 



cTSe 

 1 



77 



lif 

 1 



77 



^'t 



_l 

 1 



il 

 ) 



iT 

 _L_ 



tV 



1 

 ITS 



<2 



] 1 

 1 



\7 



_i 



87 



4^ 



J_ 

 JO 



The whole zoological region of North America being acces- 

 sible, -without much difficulty, to naturalists and collectors, that 

 highly interesting subject, the migration of birds, can be studied 

 nowhere with greater advantage. The American ornithological 

 ■works do, indeed, abound with scattered facts respecting the 

 periodical flights of some species : and the introduction to the 

 second volume of the Fauna horeuli-umericana contains a few 

 general remarks on this matter ; but a paper by the Rev. J. 

 Bachman, published in Silliman's Journal for April, 1836, is 

 the only one written expressly on the migration of North Ame- 

 i-ican birds which has ccnne to my knowledge. In this treatise 

 the mo\cmcnts of the feathered tribes in America are noticed 



