Osgood Thirty New Mice of the Genus Peromyscus. 57 



Peromyscus sonoriensis fulvus subsp. nov. 



Type from Oaxaca City, Oaxaca, Mexico. Adult male, No. 68,655, U. S. 

 National Museum, Biological Survey Collection, June 12, 1894, E. \V. 

 Nelson and E. A. Goldman. 



Characters. Similar to P. sonoriensis, but color darker and more rufes- 

 cent; skull with anterior part of z} r goma heavier and more deeply 

 notched by infraorbital foramen. 



Color. General color of upper parts russet, deepening in middle of 

 back to mars brown and Front's brown ; under parts creamy white; ear 

 tufts prominent, buffy or pale creamy ; tail sharply bicolor, brown above, 

 white below; feet and forelegs white ; outer side of ankles brownish. 



Skull. Similar to that of P. sonoriensis but more angular ; anterior part 

 of zygoma heavier and more deeply notched by infraorbital foramen ; 

 similar to that of P. labecula but smaller and shorter; zygomata not so 

 heavy nor so broadly expanding anteriorly; nasals rather short and 

 broad. 



Measurements. Type: Total length, 167; tail vertebrae, 68; hind foot, 

 22. Average of 10 adults from Chalchicomula, Puebla: 162 (150-183); 

 71.5 (65-78); 22. Skull of type: Greatest length, 25; basilar length of 

 Hensel, 19.5; zygornatic width, 12.8; interorbital constriction, 4 ; inter- 

 parietal, 8x2.1; nasals, 10; bony palate, 3.7; palatine slits, 5.6x2; 

 diastema, 6.5; postpalatal length, 8.7; upper molar series, 3.8. 



Remarks. P. s. fulvus is the southernmost representative of the well- 

 known sonoriensis group of small short-tailed mice. It is found from 

 Oaxaca north to Puebla and parts of Vera Cruz and Hidalgo. Its near 

 relatives are P. s. blandus and P. s. labecula.* In general terms, blandus 

 is small and vinaceous, fulvus is medium sized and rufescent, and labecula 

 is large and more inclined to duskiness. The intergradation of all three 

 and their connection with typical sonoriensis are scarcely to be doubted. 



Peromyscus texanus mesomelas subsp. nov. 



Type from Orizaba, Vera Cruz, Mexico. Adult male, No. 58,210, U. S. 

 National Museum, Biological Survey Collection, January 20, 1894, E. W. 

 Nelson and E. A. Goldman. 



Characters. Most similar to P. t. mearusi ; color darker; tail shorter; 

 hind foot larger; a small pectoral spot present; adolescents with an in 

 tense black dorsal stripe. 



Color. Adult: General effect of upper 'parts pale Prout's brown, pro 

 duced by fawn ground color with a liberal mixture of dusky ; sides prac 

 tically unicolor with back; no definite dusky markings about head; 

 under parts creamy white except a small but distinct pectoral spot of 

 fawn color; ears dusky with whitish edges; feet white, ankles dusky 



* Elliot, Field Col. Mus., Zool. Ser., Ill, pp. 143-144, March, 1903. 



