HOLLAND AND PETERSON: OSTEOLOGY OF THE CHALICOTHEROIDEA. 271 
The Dorsal Vertebre.” 
The dorsal vertebree of specimen No. 1604 were all found in a more or less 
perfect condition with the exception of the eighth and the eleventh. These have 
been restored in the light of other specimens belonging to other individuals and 
by accurate comparison with the vertebre immediately preceding and succeeding 
them. More or less imperfect series of dorsal vertebre belonging to other indi- 
viduals were discovered, and these have been arranged in series for purposes of 
study. 
Catalog No. 1703B. 
This series consists of the first four dorsals, the first and second of which 
have lost the posterior epiphyses of the centra, the last two of which, although 
they have sustained a few minor injuries, have preserved both the anterior and 
the posterior epiphyses. 
Catalog No. 17038C. 
This series consists of the seventh, tenth, eleventh, twelfth, thirteenth, and 
fourteenth dorsals of a small but mature individual. The epiphyses on all the 
centra are well preserved and there is every evidence of the maturity of the animal. 
These bones are referred, together with other bones placed under the general 
accession number 1703, to the species named by the writer Moropus petersoni. 
Catalog No. 1708. 
Consists of the more or less imperfect centra of dor- 
sals eleven, twelve, and fifteen. These specimens were 
found with the lumbars of the same series and bearing 
2 In measuring the dorsal vertebre it should be explained that in ascer- 
taining the greatest height a line from the anterior lower margin of the cen- 
trum to the top of the spine has in all cases been employed, as shown in the 
accompanying diagram A-B. The distance between the heads of ribs is 
measured on the side of the centrum from C—D. In all cases the greatest 
measurement is taken, even when this is not expressed in the tables. The 
only exception is in the measurement of the antero-posterior diameter of the 
spine; in taking which a point has been selected in each case just below the 
tubercular enlargement, H-F. The height of the spine from the neural canal 
to the top is measured always along the anterior face of the spine. The 
anteroposterior diameter of the spine above the neural canal is measured on 
the line G-H. In measuring the transverse diameter of the anterior face of Fie, 42. Tenth dorsal of 
the centrum a line just below the anterior faces for the heads of the ribs has Moropus elatus (No. 1604). 
been used, as this marks the widest point. The transverse measurement of Diagram to show the manner 
the posterior face of the centrum always includes the faces for the heads of of taking measurements fol- 
the ribs. owed by the author. 
