X LIST OF ILLUSTRATIONS. 



PLATE IV. 



No. 



Fig. 42. Arricola tripartita, skull from above 1949 



Fig. 43. " " skull iu profile 1949 



Fig. 44. " " left jaw, ontside 1949 



Fig. 45. " " skull from below 1949 



Fig.46. " " skull from above .- 4858 



Fig. 47. • " skull iu profile 4858 



Fig.48. " " left jaw, outside 4858 



Fig.49. " " skull /rom below 4858 



Pig. 50. " townsendi, skull from above 6892 



Pig. 51. " " skull iu profile 6892 



Fig.52. " " left jaw, outside 6892 



Fig.53. " " skull from below 6892 



Fig. 54. " xanlkognathus, skull from above 12118 



Fig. 55. " " skull in profile 12118 



Fig.56. " " left jaw, outside 12118 



Fig.57. " " skull from below 12118 



PLATE V. 



Fig. 58. Arvicola auslej'un, skull from above 1862 



Fig.59. " " skull in profile 1862 



Fig. 60. " " jaw, both sides 1862 



Fig.61. " " skull from below 1862 



Fig.62. " " skull from above 948 



Fig.63. " " skull in profile 948 



Fig. 64. " " left jaw, outside 948 



Fig. 65. '■ " skull from below 948 



Fig. 66. '• curtatus, skull from above 12169 



Fig. 67. " " skull in profile 12169 



Fig.68. " " left jaw, outside 12169 



Fig. 69. " " skull from below 12169 



Fig. 70. " pinetorum, skull from above 1930 



Fig.71. " " skull iu profile 1930 



Fig.72. " " left jaw, outside 1930 



Fig.73. " " skull from below 1930 



Fig. 74. Synaplomys cooperi, skull from above 6915 



Fig.75. ' " " skull in profile 6915 



Fig.76. " " left jaw, outside 6915 



Fig.77. " " skull from below 6915 



Note. — The numbers of the right-hand column are those of the specimens figured. 



