scott: toxodonta OF THE SANTA CRUZ beds. 
189 
the skull and dentition. It is still an open question, therefore, whether 
the differences in vertebrae and limb-bones are specific or merely 
individual. 
In two specimens the neck is nearly complete and one of these (No. 
15,000) is fortunately associated with a skull, the measurements of which 
are given in the preceding table. 
Measurements. 
No. 15,968. No. 15,000. No. 15,489. No. 15,967. No. 9192. 
Atlas, length ..... 
.069 
.078 
“ width . . . . . 
7.246 
“ height (dorso- ventral) 
•0 77 
.082 
Axis, length inch odontoid . 
.081 
•073 
.085 
“ “ excl. “ 
•055 
.051 
•059 
.060 
“ width of anterior face. 
.101 
•093 
• 113 
“ “ posterior face 
.046 
.046 
.046 
•055 
“ height, inch spine 
.097 
.105 
Cervical 3, length of centrum 
.031 
•035 
.038 
“ width of anterior face 
.042 
.042 
.044 
“ height excl. spine 
.063 
.072 
.074 
“ width over transv. proc. . 
.125 
.150 
Cervical 4, length of centrum 
•033 
•034 
•035 
.040 
“ width of anterior face 
.040 
.042 
.047 
.048 
“ height, excl. spine 
.062 
.068 
.071 
“ width over transv. proc. . 
.140 
Cervical 5, length of centrum 
.031 
•035 
•035 
.040 
“ width of anterior face 
•039 
•043 
.046 
.048 
“ height, excl. spine 
.058 
.067 
.071 
.079 
“ inch spine 
.088 
.090 
.128 
“ ant. -post, width of spine . 
.019 
.023 
.022 
.025 
“ width over transv. proc. . 
•115 
.136 
.153 
Cervical 6, length of centrum 
•034 
.030 
•035 
•033 
.042 
“ width of anterior face 
.041 
.044 
•043 
.048 
“ height, excl. spine 
.069 
.061 
.060 
.070 
.083 
“ “ “ inch spine . 
.097 
“ ant. -post, width of spine . 
.021 
.023 
.026 
.024 
.024 
“ width over transv. proc. . 
.136 
•153 
“ ant. -post width inf. lamella 
.083 
.100 
7.098 
Cervical 7, length of centrum 
.036 
•034 
.040 
•039 
.046 
“ width of anterior face 
•043 
.044 
•047 
.049 
“ height, excl. spine 
.076 
.068 
.065 
.076 
.084 
“ ant. -post, width of spine . 
.026 
.028 
.032 
.030 
.032 
