11)0 NOKTII AMKlilCAN IJIUD8. 



It would Ik3 iiuj)ossil)lo to ileseribu witli any tlo;Treo of ])iL'ci.sc'ii('.s.s tlio iniiu- 

 laeniliki vaiiatioiis in sizo, sliapc, afrnund-color, or shades of niarkiiigs, these 

 t'jilis prosoiit. Tlicy all have a certain nanu'K'ss ])hast) of rosiMiililancc, ami 

 may ho readily distiuj^uished from any other c},'gs except those of their kin- 

 dred. There are, however, certain shades of wine-eoha'ed iiiarkinf,'S in the 

 e^'^'s of the Fish Hawk of Kiiro])e, and also in that of Australia, that 1 have 

 never noticed in any eggs of the American bird; but that th'i peculiarity 

 is universal I am not able to say. The smallest egg of the caro/incmis meas- 

 ures li.Ml liy \.(>'2 inches ; the largest, ^.aCi by 1/'^ 



The European egg is smaller than the American, is often, but not always, 

 more spherical, and is less ])ointed at the smaller end. Among its varieties 

 is one which is quite conniion, and is very ilill'erent from any 1 have ever 

 observed among at least live hundred specimens of the American which I 

 have examined. 



An Osprey's egg in my collection, taken near Aarhuus, in Denmark, by 

 Ivev. H. B. Tristram, of ("a.'^tle Eden, England, nKfiisnres only 2.12 inches in 

 length, — shorter by a fourth of an inch than the smallest American, — in 

 breadth 1.G2 inches ; its ground-color is a rich cveam, with a slight tinge of 

 claret, and it is marked over its whole surface with large blotches of a beau- 

 tifully deep shade of chocolate. 



In their habits the European and the American birds seem to present 

 other decided differences. The American is a very social bird, often living 

 in large comnuinities during the breeding-season. The P^tn-ojiean is found 

 abnost invariably in solitary pairs, and frequents fresh water almost exclu- 

 sively. The American, though found also on large rivers and lakes, is much 

 the most abundant on the .sea-shore. The European bird rarely builds on 

 trees, the American almost always. The latter rarely resorts to rocky clifl's 

 to breed, the European almost uniformly do so. There is no instance on 

 record of the American species attacking smaller birds or inferior land ani- 

 mals with intent io feed on thoin. The European species is said to prey on 

 Ducks and other wild-fowl. 



Genus NATTCLERUS, Vigors. 



Kauckrus, Vio. 182.5. (Type, Foico fiircntus, LiSN ; F. forficatus, Linn.) 

 Elanoides, Oiiay, 1848. (Siuiii" type.) 



Gen. Char. Form swallow-liko, the tail cxpcssivoly lonptliened and forked, and the 

 wing.s extremely lonp;. Bill rather .small, and narrow; commissure faintly sinnated; 

 upper outline of the lower mandible very convex, the depth of the mandible at the base 

 being only about half that through the middle ; gonys drooping terminally, nearly straight. 

 Side of the head den.sely feathered close up to the eyelids. Nostril ovoid, obliquely ver- 

 tical. Feet small, but robust; tarsus about equ.il to middle toe, covered with large, very 

 irregular scales ; toes with transverse acutellic to their base ; elaws short, but strongly 

 curved; grooved beneath, their edges sharp. Second or third quill longest ; first shorter 



