LIST OF ILLUSTEATIONS. XV 



fage. 

 Pig. 102. — Peromyscus eremicua fraterculus. Skulls, a, Type of Sitomys 



herronii Bhoads; b, type of Sitomys herronii nigellus Ehoads . . 4.36 

 103. — Peromyscus eremicus fraterculus. Crowns of molar teeth. Type 



of Sitomys herronii Rhoads. o, Lower series; 6, upper series 437 



104. — Peromyscus eremicus anthonyi. Dorsal view of skull 439 



105. — Peromyscus merriami. Skull, a, Dorsal view; 6, ventral view; 



c, lateral view 443 



106. — Peromyscus merriami. Crowns of molar teeth, a, Lower series; 



6,. upper series 444 



107. — Peromyscus tiburonensis. Skull, a, Dorsal view: 6, ventral view; 



c, lateral view ..'. 445 



108. — Peromyscus tiburonensis. Crowns of molar teeth, a, Lower series; 



b, upper series - 445 



109. — Sigmodon hispidus arizonse. a, Ear; 6, forefoot; c, hindfoot; 



d, tail , 446 



110. — Sigmodon minimus. Skull, a, Dorsal view; 6, ventral view; 



c, lateral view 447 



111. — Sigmodon hispidus berlandieri. Crown of molar teeth, a, Upper 



series; b, lower-series 450 



112. — Sigmodon hispidus arizonse. Skull of type, a, Dorsal view; 



6, ventral view; c, lateral view 451 



118. — Sigmodon hispidus eremicus. Skull of type, a, Dorsal view; 



6, ventral view; c, lateral view 452 



114. — Eeithrodontomys megalotis. Skull, a, Dorsal view; 6, ventral 



view; c, lateral view 461 



115. — Reithrodontomys megalotis deserti. a, Hindfoot; 6, forefoot, 



c, tail; d, outer lateral view of lower molars; e, same of upper 



molars; /, crowns of upper molars; g, crowns of lower molars; 



h, lower incisors; i, upper incisors 462 



116. — Reithrodontomys longicauda. Skull, a, Dorsal view; 6, ventral 



view; c, lateral view 465 



117. — Neotoma cumulaton Skull of type, 'a, Dorsal view; 6, ventral 



view; c, lateral view 474 



118. — Neotoma cumulator. Crowns of molar teeth of type, a, Upper 



series; b, lower series 474 



119. — Neotorna intermedia. Crowns of molar teeth of a young individual. 



a, Upperseries; 6, lower series 485 



120. — Neotoma fuscipes macrotis. a, Ear; 6, forefoot; c, hindfoot; d, tail. 488 

 121. — Neotoma pinetorum. Skull, a, Dorsal view; b, ventral view; c, 



lateral view 490 



122. — Neotoma pinetorum. Crowns of molar teeth, a, Upper series; 6, 



lower series 490 



123. — Feet of Fiber zibethicus. a, Forefoot; 6, hindfoot 495 



124. — Tail of Fiber zibethicus. a, Lateral view; 6, dorsal view 496 



125. — Microtus ealifomicus. Skull, a, Dorsal view; 6, ventral view; c, 



lateral view.. 499 



126. — Microtus californicus. Crowns of molar teeth, li, Upperseries; 6, 



lower series 499 



