596 GEOLOGICAL SUEVEY OF THE TEREITOEIES. 



sive, and tbe posterior border of the latter extends backward with a 

 slight obliquity. 



Measurements. 



M. 



Elevation of sagittal crest above foramen magnum 0. 045 



Width of bifurcation of crest behind 033 



Width of occiput behind meatus auditorius 070 



Width between and inclusive of occipital condyles 046 



Width temporal fossa at meatus 050 



Width meatus auditorius ^ 012 



Width condyle of mandible 032 



Depth of ramus behind 095 



In further illustration of the species I add measurements of teeth, 

 &c., from another specimen : 



Ileasurements. 



M. 



Length of last two superior molars 0. 041 



Length of last 019 



Width of last 022 



Length of inferior molar series 095 



Length of premolars - 040 



Length of last molar 021 



Width of last molar . •.013 



Depth ramus at first true molar . 040 



Vertehrce. — The atlas is deeply incised anteriorly above. It is rather 

 short, and its traverse processes are flat, thin, about as long as broad, 

 and with regular convex distal margin. The arterial foramen issues 

 some distance above and within the notch which marks the anterior 

 base of the transverse process. It enters at tlie notch at the iDOSterior 

 base. The neural arch is quite convex, and its anterior margin is ob- 

 tusely rounded. The axis is near the same length, and bears a promi- 

 nent and elongate laminate neural spine. Its diai:)arapophysis is narrow * 

 and overlaps the parapophysis behind it three-quarters of an inch; it is 

 pierced for the cervical artery. The centra of the third and fourth cer- 

 vicals are about equal in length to that of the axis, but the remaining 

 ones shorten successively to the seventh, which maintains a length 

 somewhat greater than its width. The parapophyses of these, except 

 the seventh, are flattened, and have considerable antero-posterior extent, 

 their extremities overlapping. A short and rather narrow and stout 

 diapophysis is present on the sixth cervical ; on the seventh it is larger, 

 especially exi)anded autero-i)osteriorly at the base and truncate. There 

 is no parapophysis. The fourth, fifth, sixth, and seventh have strongly 

 opisthoccelian centra ; that of the third is injured. 



Measurements. * 



M. 



Length of the cervical series 0. 175 



Length of atlas, between articular faces 046 



Length of base transverse process 035 



Length of transverse process 020 



Diameter neural canal in front 021 



Diameter of anterior expanse 050 



Diameter of total exjianse 099 



Length axis along basis neural arch 021 



Elevation crest (rectangular) from posterior zygapophysis 036 



Length parapophysis of fifth cervical on margin . 051 



Extent zygapophyses of fiftli cervical on margin 048 



Exijause zygapophyses of fifth cervical on margin behind 044 



Elevation neural spine ofC.6 056 



Elevation neural sj)iue ofC.7 075 



Length centrum below ofC. 7 028 



Diameter of cup, about ,. 032 



