312 MEMOIRS OF THE CARNEGIE MUSEUM. 
Height of metapophysis above prezygapophysial face........................- 12 13 19 
Height of metapophysis above transverse procesS..............-0e0e++seeeeees 75 54 58 
Antero-posterior diameter of metapophysis below..............-....-.-----+s- 45 32 35 
Antero-posterior diameter of metapophysis at end........................---- 80 22 27 
Distancevacrossiends of metapophyseseee ea ae eee eerie ae 112 74 105 
The Fifth Lumbar Vertebra. 
In effecting a restoration of the mounted skeleton the centrum of the fifth 
lumbar vertebra belonging to specimen No. 1708 was employed. The centrum in 
this case was slightly injured on its anterior and posterior surfaces below and only 
retained the bases of the transverse processes and some portions of the pedicels. 
In the light of more perfect material, however, a satisfactory restoration was 
possible. No. 1708C is a practically perfect specimen (see Fig. 71), having only 
Fig. 71. Fifth lumbar vertebra of M. petersoni (No. 1708C). X43. 
sustained a few minor injuries at the extremities of the transverse processes. 
Specimen No. 1718 is likewise a perfect specimen except for the loss of the anterior 
epiphysis of the centrum; the posterior epiphysis remains. Specimen No. 17144 
represents a small and immature individual probably belonging, as does also 
specimen No. 1703C, to M. petersoni. The immaturity of specimen No. 1714A is 
shown by the loss of the anterior and posterior epiphyses of the centrum. The 
left metapophysis has been lost and the extremity of the left transverse process 
has sustained considerable injury. In other respects the specimen is quite perfect. 
In studying the specimens of the fifth lumbar it is noticeable that the anterior 
and posterior articulating surfaces of the centrum have become greatly compressed 
