500 J. A. ALLEN ON BIRDS 



77. Circus hudsonius Vieill. Marsh Hawk. Seen almost daily, flying low and rapidly over 

 the prairies. The only Hawk seen habitually on the open prairie. 



78. Nauclerus furcatus Vigors. Swallow-tailed Hawk. Common. Often seen in consid- 

 erable numbers, and generally over or near the timber skirting the streams. At Denison, in 

 the timber of the Boyer Elver, they were very common and nesting; the nests being placed 

 on horizontal branches, at some distance from the trunk. By the middle of July the youno- 

 had not flown. With a peculiarly graceful, swallow-like flight this beautiful bird was seen 

 not infrequently skimming over the prairies, singly or two or three in company, eagerly 

 searching for their reptile food. ° 



Vultukid^!. 



79. Cathartes aura l\V Turkey Buzzard. Common, and generally distributed. On several 

 occasions I saw them collected about the carcass of a dead animal in considerable numbers. 

 At Panora I once saw them congregated in hundreds, attracted by two dead pigs. Fre- 

 quently observed them resting on the fences and wheat stacks, in very hot days opening their 

 wings to catch the breeze, the very pictures of indolence. In southern Guthrie County is a 

 locality known as « Buzzards' Roost," it is said from the number of these birds that resort 

 there 



COLUMBID^!. 



80. Zencedura carolinensis Bon. Mourning Dove. Very abundant, and almost domestic. 



MELEAGRrDrDJE. 



81. Meleagris gallopavo Linn. Wild Turkey. Said to have been rather common about the 

 groves when the country was first settled, and to exist in small numbers still. 



TETRA0NIDJ3. 



82. Cupidonia cupido Bd. Prairie Hen. Generally abundant. This season rather scarce ; 

 owing to the extreme wetness of the spring and early summer few young were raised'. 

 Rarely any but old birds seen, which were shy and hard to get. Exclusively a prairie 

 bird, as its name indicates. At Boonesboro it was said to have the singular habit, 



Bryant has remarked (Proc. Bost. Soc. Nat. Hist. Vol. VII, C. brazUiensis, of South America, there is a correspondence in 

 107), as well admit twenty, or extend the number almost in- their relative distribution in the higher latitudes on each side of 

 definitely. The spec.es of Buteo already admitted by different the equator which seems to strongly indicate their identity 

 authors, for temperate North America, numbering twelve to But, in fact, we are now able to trace both of our North Amer- 

 fifteen, is an altogether improbable number, considered in refer- ican species across the tropics. In North America the C aura 

 ence to the evidence furnished on this point by what is known 111. exceeds the range northwards of C. atratus Less by about 

 of the general d.stnbution of these birds; while in the additional twelve degrees of latitude, C. aura reachin-r in summer in the 

 light of the well-known variability of its representative of the interior, nearly or quite to the 55th paralfel, while C 'atratus 

 Eastern Continent, Buteo vulgaris, it becomes quite incredible, has not been traced above the 42d. At the south C aura ex- 

 Judging from the whole number of undoubted species of this tends in summer to the Falkland Islands and the southern ex- 

 family now known, and their relative distribution in different tremity of the southern continent, (Lat. 52° to 54° south) 

 countries, we have apparently no good reason to expect more while C. atratus has not been reported below the 40th or 41st 

 than the three or four well-marked ones of this genus, which parallel. The smaller size of specimens from Brazil, compared 

 we certainly have, as enumerated above. Again, the wide with those of the United States, which has been dwelt on as 

 range of individual vanation, especially in color, which emi- the chief distinction, is only what we should expect from what 

 nently marks all the Falconi.he, renders the characters assigned seems a general law of size among birds - a diminution with 

 for many ol our Buteos of little weight. the decrease of latitude and increase of temperature in species 

 While no character has been adduced showing satisfactorily having a wide range in latitude, and which hundreds of species, 

 specific diversity between C. aura 111. and C. atratus Less., of in both hemispheres, exemplify. 

 North America, and their supposed distinct allies, C.jota and 



