18 



NOETH AMEEICAN FAUNA. 



[No. 40. 



anzonensis is large, and skulls from Nebraska, Kansas, Oklahoma, 

 and Texas are sometimes difficult to distinguish. As here mapped 

 the range of C. I. ludovicianus includes the entire area where typical 

 examples most frequently occur. The characters separating ari- 

 zonensis are slight and are only average. For example, in an exami- 

 nation of 120 adult skulls from Montana, the Dakotas, Arizona, 

 and Chihuahua, about 80 per cent can readily be placed with their 

 proper form; comparing 115 skulls from Wyoming, ^Nebraska, and 

 New Mexico, about 75 per cent are easily determinable; 31 skulls 

 from Colorado and extreme western Texas (west of Pecos River) still 

 show about 75 per cent readily distinguishable; while of 56 skulls 

 from Kansas and Texas east of the Pecos, there are just about 50 per 

 cent which can be differentiated, and the characters are relatively 

 hard to distinguish satisfactorily. 



An albinistic specimen, entirely white, from the Central Park 

 Menagerie, New York, has been examined in the collection of the 

 American Museum of Natural History. 



Specimens examined. — Total number, 290, as follows: 



Colorado: Boulder County, 1; Colorado Springs, 1;^ Denver, 1; Don Carlos, 1; 

 Fremont County, 1;2 Larimer County, 4 Loveland, 3; Monon (Baca County), 

 2;i Olney (Otero County), 4; Pueblo, 1; Rockvale, 2f Soda Springs, 2;* 

 Springfield, 2.^ 



Kansas: Arkansas River, 1; Banner, 8; Cairo, 2; Coyote Station, 1;* Fort Hays, 

 8;* Garden City, 2f Garden Plain, 1; Hoxie, 1; Long Island, 3;^ Pendennis 

 (Lane County), 1; Republican River, 1; Trego County, 6. 



Massachusetts: Nantucket, 2 (introduced).'* 



Montana: Billings, 1; Boxelder Creek, 1; Calf Creek, 1;^ Craig (10 miles 

 northwest of), 1; Damall's Ranch, 1; Fort Assinniboine, 5; Fort Custer, 3; 

 Glendive, 6; Great Falls, 2; Milk River (near mouth), 2; Newland, 2; Pom- 

 pey's Pillar, Yellowstone River, 1; Shelby Junction, 4; Teton River, 2; 

 Tilyou's Ranch, 1. 



Nebraska: Alma, 2; Birdwood Creek, 3; Columbus (Platte County), 1; Ken- 

 nedy, 3; Platte River, 4. 



New Mexico: Chico Springs, 1; Koehler Junction, 2; Pecos, 1; Tompkin'e 

 Lake, 2. 



North Dakota: Glenullin, 2; Little Missouri River, 1; Medora, 7. 

 Oklahoma: Beaver River, 4f'^ Chattanooga, 1; Moimt Scott post office, 3; 



Neutral Strip, bf>^ Ponca Agency, 2; White Horse Spring, 5 (including type 



of ^'pyrrotrichus'').^ 



South Dakota: Armour, 1; Buffalo Gap, 8; Cheyenne River (Custer County), 

 2;^ Corral Draw, 3;^ Edgemont, 2; Fort Pierre, 6; Fort Pierre to Badlands, 

 15 (skulls); Fort Randall, 11; Phinney (Cheyenne River), 1; Pine Ridge 

 Indian Reservation, 1;^ Rapid City, 10; Upper Missouri River, 3 (skulls and 

 skeletons). 



Texas: Brazos River, 1; Colorado, 1; Fort Chadboume, 1;* Henrietta, 4; Lips- 

 comb, 1; Llano Estacado, 1; Mason, 9; Monahans, 1; Red River, 2; Stanton, 

 2; Texline, 1; Vernon, 11; Wichita Falls, 3. 



1 Collection E. R. Warren. 



2 Collection Field Mus. Nat. Hist. 



8 Collection Amer. Mus. Nat. Hist. 

 * Collection Mus. Comp. Zool. 



