_P. f. callistus_ is distinct cranially from all other subspecies of _P. fasciatus_ in the narrowness of the interparietal, the greater length of the tympanic bulla and the greater mastoidal breadth. The fine, silky nature of the pelage is shared, to some extent, with _P. f. litus_. A specimen from 27 mi. N, 37 mi. E Rock Springs, Wyoming, referred to _callistus_ resembles _litus_ in pale dorsal coloration and slightly wider interparietal. Four immature specimens from 25 mi. N, 38 mi. E Rock Springs, also referred to _callistus_, have extremely pale juvenal pelage and also are judged to be intergrades with _litus_. _Specimens examined._--Total number, 23, as follows: WYOMING: _Sweetwater County_: 18 mi. S Bitter Creek, 6800 ft., 3 (KU); Kinney Ranch, 21 mi. S Bitter Creek, 6800 ft., 9 (KU 7, USBS 2); 30 mi. S Bitter Creek, 2 (KU); 33 mi. S Bitter Creek, 6900 ft., 2 (KU); 32 mi. S, 22 mi. E Rock Springs, 7025 ft., 2 (KU); 25 mi. N, 38 mi. E Rock Springs, 6700 ft., 4 (KU); 27 mi. N, 37 mi. E Rock Springs, 6700 ft., 1 (KU). TABLE 1.--CRANIAL MEASUREMENTS OF PEROGNATHUS FASCIATUS Column Headings: A: Sex and number of individuals averaged or catalog number B: Occipitonasal length C: Frontonasal length D: Basal length[1] E: Mastoidal breadth G: Interorbital breadth H: Interparietal breadth I: Cranial depth J: Length of tym. bulla K: Length of maxillary tooth-row Symbols: F: [Female] M: [Male] ========================================================================== [A] | [B] | [C] | [D] | [E] | [G] | [H] | [I] | [J] | [K] -----------+-------+-------+-------+-------+-----+-----+------+-----+----- | _P. f. fasciatus_, topotypes 6, 4 [M] | | | | | | | | | and 2 [F] | 23.3^5| 15.5^5| 18.4 | 12.3 | 5.3 | 4.9 | 8.7 | 7.3 | 3.3 min. | 22.9 | 14.9 | 17.8 | 12.1 | 5.1 | 4.8 | 8.6 | 7.0 | 3.2 max. | 24.2 | 16.5 | 18.9 | 12.8 | 5.5 | 5.1 | 9.1 | 7.6 | 3.4 -----------+-------+-------+-------+-------+-----+-----+------+-----+----- | _P. f. olivaceogriseus_, holotype [M] 97941 | | | | | | | | | MVZ | 22.1 | 14.5 | 17.4 | 12.0 | 5.2 | 4.6 | 8.3 | 7.3 | 3.5 -----------+-------+-------+-------+-------+-----+-----+------+-----+----- | Various localities in eastern Wyoming 6, 5 [M] | | | | | | | | | and 1 [F] | 22.8 | 15.0 | 18.0 | 12.4^5| 5.0 | 4.9 | 8.4^5| 7.3 | 3.3 min. | 22.2 | 14.5 | 17.5 | 12.2 | 4.9 | 4.7 | 8.1 | 7.1 | 3.3 max. | 23.7 | 15.7 | 18.6 | 13.0 | 5.1 | 5.2 | 8.6 | 7.6 | 3.5 -----------+-------+-------+-------+-------+-----+-----+------+-----+----- | _P. f. infraluteus_, topotypes 4, 3 [M] | | | | | | | | |