Part 11

Comparison.--From Zapus trinotatus trinotatus, Z. t. montanus differs as follows: Size averaging smaller; sides more ochraceous, fewer black hairs; upper parts duller; skull smaller; zygomatic arch shorter, braincase relatively narrower; frontal region more inflated; pterygoid fossae relatively narrower; zygomata narrower.

Remarks.--The systematic status of Z. t. montanus has been in doubt. Several workers, for example, Howell (1920:227) and Preble (1899:28), considered it to be a species, and others (Merriam, 1897a:104, Bailey, 1936:234) considered it to be a subspecies of Z. trinotatus. Z. montanus is here considered to be a subspecies of Z. trinotatus, because of the agreement of the two in size and shape of the baculum, diameter and pigment pattern of the hair, and the over-all proportions of the skull. In addition, animals from intermediate geographic areas are available and show actual intergradation.

Intergradation has been noted in specimens from North Santiam River, 3400 ft., Oregon. In color, in length of incisive foramina, in breadth of braincase, and in width of zygomata these specimens are intermediate between Zapus trinotatus montanus and Z. t. trinotatus, but in the sum-total of characters they are referable to the former. Specimens from Lost Creek R. S., 10 mi. SE McKenzie Bridge, are intermediate in color between Z. t. trinotatus and Z. t. montanus; they are referable to Z. t. montanus. The animals available from Brooks Meadow, 4300 ft., 9 mi. ENE Mt. Hood and the one from Mt. Hood, in color, in length of incisive foramina, and in mastoid width, closely approach Z. t. trinotatus from Skamania County, Washington, but in the sum-total of characters are nearest Z. t. montanus and are here referred to montanus.

Specimens examined.--Total, 35, all from Oregon, distributed as follows: Deschutes County: Tumalo Creek, 15 mi. W Bend, 6100 ft., 3 (MVZ). Douglas Co.: Diamond Lake, 1 (USBS). Hood River Co.: Brooks Meadow, 4300 ft., 9 mi. ENE Mt. Hood, 10 (MVZ); Mt. Hood, 1 (USBS). Klamath Co.: Crater Lake, 3 (MVZ); 1/2 mi. N Government Camp, 6700 ft., Munson Valley, Crater Lake Nat'l Park, 2 (MVZ); east slope Cascade Divide, 6400 ft., Crater Lake Nat'l Park, 2; Anna Creek, Mt. Mazama, 6000 ft., 2 (USBS). Lane Co.: Lost Creek R. S., 10 mi. SE McKenzie Bridge, 6 (USBS); Three Sisters, Alder Springs, 4300 ft., 2 (USBS). Linn County: North Santiam River, 3400 ft., 3 (MVZ).

Marginal records.--Oregon: Brooks Meadow, 4300 ft., 9 mi. ENE Mt. Hood; Tumalo Creek, 15 mi. W Bend, 6100 ft.; Anna Creek, Mt. Mazama, 6000 ft.; east slope Cascade Divide, 6400 ft., Crater Lake Nat'l Park; Diamond Lake; North Santiam River, 3400 ft.

=Zapus trinotatus orarius= Preble

Zapus orarius Preble, N. Amer. Fauna, 15:29, August 8, 1899.

Zapus pacificus Merriam, Proc. Biol. Soc. Washington, 11:104, April 26, 1897 (part--the part from Point Reyes, Marin County, California).

Zapus trinotatus orarius, Hooper, Miscl. Publ. Mus. Zool. Univ. Michigan, 59:67, January 12, 1944.

Type.--Male, adult, skin and skull, No. 250, collection of E. A. and O. Bangs (now in Mus. Comp. Zool.); Point Reyes, Marin County, California; obtained on May 14, 1893, by C. A. Allen, original No. 618.

Range.--Southern and western Marin County, California. Zonal range: Upper Sonoran areas that are moist yet safe from continuous inundation.

Description.--Size small; back dark ochraceous, usually overlaid with black hairs forming broad dorsal band; side lighter than back with admixture of black hairs; lateral line distinct, usually bright, near Ochraceous-Buff; under parts strongly suffused with ochraceous; tail bicolored, white to yellowish-white below and dark brown above; feet grayish-white above; ears dark, edged with yellowish-white or tan; skull small; zygomata narrow; braincase narrow; maxillary tooth-rows short; interorbital region narrow; incisive foramina short; palatal bridge relatively long; mastoid region relatively broad; occipitonasal length short.

Comparison.--From Zapus trinotatus eureka, Z. t. orarius differs in: Size smaller; color, dorsally and laterally, brighter, more ochraceous; skull averaging smaller in all measurements taken except length of palatal bridge, where it averages longer; auditory bullae smaller, less inflated; pterygoid fossae narrower.

Remarks.--Preble (1899:30) named this jumping mouse as a full species. Included in the specimens examined were animals from Eureka and Mad River, Humboldt County, California. Howell (1920:231) retained Z. orarius as a full species but restricted its range to Marin County, California, and referred material from northern California, including the animals from Eureka and Mad River, to a new subspecies (eureka) of the species Z. trinotatus. Howell (loc. cit.) suggested that Z. orarius had its closest affinity with Z. t. eureka but remarked that intergrading material was not available. Hooper (1944:68) arranged Z. orarius as a subspecies of Z. trinotatus and suggested that intergrades could be expected from geographically intermediate areas, for example, northern Sonoma County, California.

Although animals from intermediate geographic areas still are not available to show actual intergradation, I concur with Hooper (loc. cit.) and arrange Z. orarius as a subspecies of Z. trinotatus. The close relationship of Z. orarius to Z. trinotatus is evident; certain diagnostic characters, held in common, are the shape and size of the os penis, the diameter and pigment pattern of the hair, and the general configuration of the skull.

Interbreeding in the wild between Z. t. orarius and Z. t. eureka probably does not take place, because these subspecies are separated by terrain unsuited to jumping mice.

Specimens examined.--Total, 29, all from California, distributed as follows: Marin County (MVZ): 3 mi. W Inverness, 300 ft., 14; 5 mi. NNE Point Reyes Lighthouse, 12; W end Elk Valley, 10 ft., 1; West Portal, Fort Barry, 2.

Marginal records.--California: 3 mi. W Inverness, 300 ft.; West Portal, Fort Barry.

=Zapus trinotatus trinotatus= Rhoads

Zapus trinotatus Rhoads, Proc. Acad. Nat. Sci. Philadelphia, 1894:42, January 15, 1895.

Jaculus hudsonius, Baird, Repts. Expl. and Surv. 111, 8 (pt. 1): 433, July 14, 1858 (part--the part from Washington).

Zapus hudsonius, Coues, Bull. U. S. Geol. and Geog. Surv. of the Territories, 2nd ser., No. 5:260, 1877 (part--the part from Steilacoom [Pierce County], Washington).

Zapus imperator Elliot, Field Columbian Mus., publ. 30, zool. ser., 1:228, February 1, 1899, type from Siegs Ranch, Elwah River, Clallam County, Washington.

Zapus princeps trinotatus, Dalquest, Univ. Kansas Publ. Mus. Nat. Hist., 2:371, April 9, 1948.

Type.--Male, adult, skin and skull, No. 360, S. N. Rhoads Coll.; Lulu Island, mouth of Frazer River, British Columbia; obtained on May 31, 1892, by S. N. Rhoads (type in Philadelphia Acad. Nat. Sci.).

Range.--Pacific coastal region from Requa, Del Norte County, California, north in Oregon west of the Cascades, and in Washington including the Cascades; to southwestern British Columbia.

Description.--Size large; back from near Ochraceous-Buff to near Tawny with admixture of black hair forming broad dorsal band; sides lighter than back from near Ochraceous-Buff to near Tawny; lateral line usually distinct; belly white, sometimes with faint suffusion of ochraceous on lower throat and upper chest; tail bicolored, brown above, white to yellowish-white below; ears dark, sometimes flecked with color of sides, edged with ochraceous; feet grayish-white above; palatal bridge relatively short; incisive foramina relatively long; condylobasal region long; zygomatic width great; braincase relatively broad; distance from incisors to postpalatal notch relatively great.

Comparisons.--For comparisons with Zapus trinotatus montanus and Zapus trinotatus eureka see accounts of those subspecies.