| A | B | C | D | E | F | G | H | I | J | |
| D. o. largus, type locality (K.U.) | ||||||||||
| Mean (9) | 226 | 117 | 35.8 | 36.3 | 21.5 | 19.2 | 3.6 | 13.7 | 12.6 | 23.2 |
| Maximum | 241 | 128 | 37 | 37.2 | 22.0 | 19.9 | 3.7 | 14.2 | 13.9 | 23.9 |
| Minimum | 212 | 105 | 35 | 35.2 | 20.7 | 18.6 | 3.5 | 13.5 | 11.6 | 22.3 |
| D. o. compactus, type locality (U.S.N.M.) | ||||||||||
| Mean (10) | 230 | 126 | 37.7 | 36.6 | 22.1 | 20.0 | 3.8 | 14.0 | 12.5 | 23.8 |
| Maximum | 241 | 135 | 40 | 37.8 | 23.2 | 21.4 | 4.0 | 14.5 | 13.1 | 24.4 |
| Minimum | 208 | 118 | 35 | 35.5 | 21.6 | 19.2 | 3.6 | 13.1 | 11.3 | 23.1 |
| D. o. parvabullatus, type locality and 2 mi. S of same (K.U.) | ||||||||||
| Mean (7) | 216 | 111 | 35.9 | 36.4 | 21.7 | 19.6 | 3.6 | 13.8 | 12.1 | 23.0 |
| Maximum | 222 | 113 | 37 | 36.9 | 22.1 | 20.7 | 3.8 | 14.2 | 12.5 | 23.5 |
| Minimum | 210 | 109 | 34 | 35.9 | 21.3 | 19.1 | 3.3 | 13.4 | 11.6 | 22.1 |
| D. o. sennetti, 2 mi. S Riviera, Texas (after Setzer, op. cit. :565) | ||||||||||
| Mean (5) | 218 | 112 | 35.8 | 37.2 | 23.4 | 20.1 | 4.0 | 13.6 | 13.1 | 24.2 |
| Maximum | 222 | 115 | 38 | 38.2 | 24.1 | 20.7 | 4.3 | 14.4 | 13.2 | 24.6 |
| Minimum | 208 | 104 | 34 | 36.3 | 23.0 | 19.4 | 3.8 | 13.0 | 12.6 | 23.8 |
Dipodomys ordii largus new subspecies
Ord Kangaroo Rat
Type.—Female, adult, skull and skin, No. 27234, Mus. Nat. Hist., Univ. Kansas, from Mustang Island, 14 mi. SW Port Aransas, Aransas County, Texas; obtained 30 June 1948 by W.K. Clark; original No. 543.
Range.—Known from Mustang Island only.
Diagnosis.—Size medium (see measurements). Color pale, and as described for D. o. parvabullatus. Skull small; auditory bullae (actually and relative to remainder of skull) smaller than in any other known kind of Dipodomys, except D. o. parvabullatus in which breadth across bullae is approximately the same; notably narrow across maxillary processes of zygomatic arches.
Comparisons.—From Dipodomys ordii sennetti (J.A. Allen) of the mainland, D. o. largus differs in: Color paler on pigmented areas; white areas more extensive; skull averaging smaller except in basilar length and length of nasals which are approximately the same as in D. o. sennetti. From Dipodomys ordii compactus True of Padre Island, D. o. largus differs in: Body longer; tail shorter; skull narrower across tympanic bullae and across maxillary processes of zygomatic arches; nasals shorter. From Dipodomys ordii parvabullatus of the coastal island south of Padre Island, along the gulf coast of Tamaulipas, D. o. largus differs in: Body and tail longer; basilar length of skull averaging less; breadth across maxillary processes of zygomatic arches greater; premaxillae not extending so far behind nasals.
Remarks.—D. o. largus resembles D. o. compactus in external proportions and D. o. parvabullatus in cranial proportions. The degree of difference between D. o. compactus and D. o. largus is less than between D. o. compactus and D. o. parvabullatus. To me, the three subspecies mentioned in the preceding sentence are indistinguishable in color.
Two of the eleven specimens of D. o. largus are of the light color phase (upper parts Cartridge Buff) whereas all but two of the eleven specimens of D. o. compactus are of the light color phase. Each of the cheek-teeth of the upper jaw of D. o. largus has a complete ring of enamel around the dentine of the occlusal surface, as described by Setzer (Univ. Kansas Publ., Mus. Nat. Hist., 1:517, December 27, 1949) for D. o. compactus. The upper dentitions of ten specimens of D. o. compactus examined by me in this respect reveal a total of only five teeth (in four individual animals) that have the enamel ring incomplete; one premolar and three molars are incomplete on the lingual side and one molar is incomplete on the labial side.