8 BULLETIN 50, UNITED STATES NATIONAL MUSEUM 



Mathercfsia Ikedale, Bull. Brit. Orn. Club, xxvii, 1910, 47. (Nom. nov. pro 



Antigone Reichenbach, 1853, not Antigone Gray, 1847.) 

 Matheiosena Ibedale, Austr. Av. Rev., ii, 1814, 82 (Nom. nov. pro Mathewsia 



Iredale, 1911, not Mathewsia Saulcy, 1868.) 



Generic characters. — Bill lengthened, straight, the upper mandible 

 only slightly decurved at the extreme tip ; the commissure and other 

 outlines straight. Nasal groove very large and open, extending over 

 the basal two-thirds of the bill. Nostrils broadly open, pervious; 

 the anterior extremity halfway from the tip of bill to eye. The 

 upper half of the head naked, warty, but with short hairs. 



Legs much lengthened; toes short, hardly more than one-third 

 the tarsus. Inner toe rather longer than the outer, its claw much 

 larger. Hind toe elevated, short. Toes connected at the base by 

 membrane. Tarsi broadly scutellate anteriorly. Tertials longer 

 than the primaries, decurved, their webs in some species decomposed; 

 first quill not much shorter than the second. 



This genus is nearly cosmopolitan, each of the great continents, 

 except Africa and South America, possessing its peculiar species; 

 South America is without a single representative of the family. 

 Asia comes first in number of species (seven), North America coming 

 next, with two, while Europe and Australia possess only one each — 

 the former in common with western Asia (and wintering in Africa). 



KEY TO THE AMERICAN SPECIES AND SUBSPECIES OF GRUS 



o. Tarsus usually 275 mm. or more ; bill stout, its depth through the base about 

 one-fourth the length of the culmen ; distance from posterior end of nostril 

 to base of upper mandible much more than one-half the distance from 

 anterior border of nostril to tip of upper mandible. 

 &. Cheeks bare ; plumage pure white except for black primaries. 



Grus americanus, ad. (p. 9) 

 &6. Cheeks feathered; plumage white heavily washed with buffy ochraceous. 



Grus americanus, young (p. 9) 



aa. Tarsus under 260 mm. ; bill more slender ; its depth through base less than 



one-fourth the length of the culmen ; distance from posterior end of nostril 



to base of upper mandible less than one-half the distance from anterior 



end of nostril to tip of upper mandible. 



6. Entire plumage deep slate-gray, sometimes tinged with rusty; forehead 



and anterior part of crown with unfeathered, red, warty skin. 



c. Size smaller, exposed culmen usually under 100 mm. in length, almost 



never more than 110 mm Grus canadensis canadensis, ad. (p. 14) 



cc. Size larger, exposed culmen always well over 110 mm. in length. 

 d. Hind neck and occiput paler — pallid mouse gray to pale mouse gray. 



Grus canadensis tabida, ad. (p. 20) 

 dd. Hind neck and occiput darker — light mouse gray to mouse gray, 

 e. Tarsus shorter, under 215 mm_Grus canadensis nesiotes, ad. (p. 26) 

 ee. Tarsus longer, 220 mm. or over, 



Grus canadensis pratensis, ad. (p. 25) 

 &&. Entire plumage brownish washed with rusty; head completely feathered. 



Grus canadensis, all races, juv. 



