266 U. 8S. P. R. R. EXP. AND SURVEYS—ZOOLOGY—GENERAL REPORT. 
doubt whatever that, with very few exceptions, the many species described by Audubon and 
Bachman as from California are really from Southern Mexico, adjacent, perhaps, to southern 
California, and have no right to a place in a fauna of North America, certainly not of the 
United States. 
Detailed measurements of a specimen in alcohol. 
Tip of nose to— Tail to end of— Length of— 
Current | Sex. Locality. 
number. 
Eye. | Ear. |Occip.| Tail. | Vert. Hairs. | Fore ft. | Hind ft. 
| " 
2413 ° Petaluma, Calo; 2252.22. - 22 1.35 | 2.45 | 2.8 |11.25 | 11.5 14. 75 2. | Hei! 
List of specimens. 
x E 
2 pis. 5 Measurements. 
| aS — SS 
a | Sea) oo . E 
[hen || en Locality. When col- Whence obtained. = | Nature of spe-|Head| Tail. Collected by— 
& |ac] z lected. 3 cimen. and 
Sites us & body. 
Ss Ea ¥ & Pe... 
3 6 3 | = Vert. Hairs, 
o |}|o n | ° 
—_— — SSS —S Ss | Se 
| 
AD see © | Fort Dalles, O. T......| Jan. 17, 1855.) Dr. Geo. Suckley...... 36 | SKin coc. ccccccleenves {12.50 
1003 | 2010| @ je..s.... GO: scccsscvecses Jan. 15, 1855.) cceces cece dO cece cevcee BT ocr cee cocvece 11.25 |10.60 | 
1004 | 2011 ie) eccccece dO. seevece eeneee Jan. 15, 1855.}.000ccceee dO ..sseveeees 38 |. .dO...s cesseses 11750 |11,00'|14,25 | ...5. ccceceemeeueeen 
1175 |......| ****+| Fort Jones, Cal........ 1855. Lt. R.S. Williamson,..,)..+...|.- Dr. J. S. Newberry. 
1173 | Q117 | +--+ Stockton, Cal....ss.00+ Weceeee ceccvcleccees ces dO cscvees seeeleeeeee GO .e cee ceccee|secceslevecns|seeeeslsecencee dO .eceve 
2413 |...... QO | Petaluma, Cal .........|....0seeee eee. E. Samuels.....+ sesese} 14 oss caieeacmcipaebien ae 
G09 |. .eeclaeeeee San Francisco, Cal.....|.. eet eeee eooe| R. D. Cutts neers eeeeeeleneeee eee sees cece 
BAGS | edesd|=seesalaese once COvecaale alas nosis Lt. W. P. Trowbridge... eevee auee vovdecvectcbicess 
L174 | occas secveclencevcee Oveccens eocase ede, cevcceces| voceesleees. +eeee-| Dr. J. S. Newberry. 
480 | 1604 |...... Fort Tejon, Cal... .... eoceceteccetes Mounted ......|- aveelsavcee|cevece Dr.A. L. Heermann. 
2462 |..eees seeees| San Diego, Cal,......, seeeee erences Dr. Thomas H. Webb..)....++ SKIN. ceeec esl eeeeeeleeeee s|eveseeleccececesees eeeeeee 
SCIURUS CASTANONOTUS, Baird. 
Chestnut Backed Squirrel. 
* 
Sciurus castanotus, Barrp, Pr. A. N. Sc. Phila. VII, April, 1855, 332. (Typographical error for castanonolus.) 
Body about 11 inches. Tail, with the hairs, but little longer. Hind feet 2.60 inches, skull, 2.40. 
Size about that of S. cinereus. Five permanent molars in the upper jaw. Tail about equal in length to the body, not 
bushy. Ears with rather short hairs, not tufted. Soles naked in winter. Back deep chestnut brown; rest of upper parts 
mixed ash, gray, and lead color. Eyelids, upper surfaces of feet, and whole under parts white. Ears and sides of head 
ash gray. The sides, tip, and under parts of tail, pure white; above (within the margin) mixed black and white. 
A detailed description of this squirrel will be found in the report of the Zoology of the United States and Mexican 
Boundary Survey. 
This species bears a very close resemblance to S. aberti and may prove to be the same, 
although there are abundant differences. The most striking characteristic is the absence of the 
beautiful ear tufts of S. aberti. Some of our squirrels which have smooth ears in summer are tufted 
in winter, but as the Coppermines specimens were caught in winter, it is not likely that they are 
ever tufted. The tufts, too, of S. aberti are long hairs growing from the very margins of the 
ears and projecting an inch beyond. The convexity of the ear and a woolly space at their 
