28 



PROCEEDINGS OF THE NATIONAL MUSEUM 



VOL. G6 



the size of the neural canal in accordance with their position in the 

 column. Anteriorly the neural canal is wider than high, but pos- 

 teriorly (pi. 7, fig. 8) the reverse is true. The centra of all these 

 dorsals are very slightly flattened dorsally and constricted mesially. 

 The centra of the posterior dorsals are deeper and more rounded in 

 cross section. There is a thin-edged longitudinal ridge or carina 

 on the dorsal faces of the centra of the third, fifth, ninth, tenth, and 

 eleventh dorsals. 



Measurements of dorsal vertehrae {in millimeters) 



Greatest depth (vertically) of vertebra (tip of 

 neural spine to inferior face of centrum) 



Greatest depth of neural canal anteriorly 



Greatest breadth of neural canal posteriorly .. 



Height of anterior face of centrum 



Breadth of anterior face of centrum 



Height of posterior face of centrum 



Breadth of posterior face of centrum 



Length of centrum 



Distance across vertebra between tips of the 

 diapophyses 



Distance across vertebra between tips of 

 transverse processes (parapophyses) 



Distance across vertebra between tips of pre- 

 zygapophyses- 



Distance across vertebra between outside 

 margins of the postzygapophysial facets 



Distance between tip of left postzygapophysis 

 and tip of left prezygapophysis 



Minimum length of neurapophysis 



Anteroposterior length of neural spine in a 

 horizontal line immediately above the 

 zygapophyses .-. _ 



Anteroposterior diameter of right diapophysis 

 at extremity 



Anteroposterior diameter of right parapophy- 

 sis at extremity - 



Vertical height of neural spine (distance be- 

 tween superior margin of neural canal and 

 tip of spine) - 



Third 



130+ 

 29.5 

 37.2 

 39 

 42 

 38+ 

 53+ 



2 36 



114 



68 

 53.7 



58.7 

 20.2 



30.5 

 21.4 



61+ 



Fifth 



131+ 

 27 



34.5 

 38.2 

 43.4 

 35.5 

 51.7 



144.2 



96.8 



51.2 

 33.4 



65 

 22.1 



36 

 32.7 



62.1 



Sixth 



110. 2+ 



23.7 



30.2 



33.5+ 



46.4 



35+ 



56.2 

 8 35+ 



4.5 



28.6 



49.5 

 20.4 



36 

 25.5 



49.7 



Seventh 



97+ 



27.6 



27.2 



41.4 



46.7 



41.7+ 



48.8+ 



'48.7 



83.3 



45.7 

 18.5 



73.2 

 26 



Ninth 



129.7 

 28 

 20.5 



Tenth 



143.2 

 32.7 

 20.5 



45.2 : 47.5 



53.6 i 54 



47 i 46.6 



50. 2 52. 8 

 57.5 



57.2 



66 



29.4 



16.5 



66+ 

 35.8 



45.5 

 15.4 



52 



97 

 ^.3 



73.5+ 

 40.7 



45 



34.3 



Elev- 

 enth 



132.7 



29.5 



20.7 



48 



53.6 



48+ 



54.2+ 

 160.6 



128.2 



11.7 



82.2 

 42.3 



49.2 



33.3 



55.5 



1 One epiphysis missing. ' Both epiphyses missing. 



LTJMBAB VEETEBRAE 



Before taking up in detail the characteristics of the three lumbars 

 found with the skull, mention should be made that on the basis of 

 Abel's restoration they appear to represent the sixth, eighth, and 

 tenth in the series. The right parapophysis of the sixth lumbar 

 (pi. 8, fig. 5) is broken off near the base. Beyond the lengthening 

 of the neural spine and a slight narrowing of the neural canal, there 

 is no marked difference between the eighth (pi. 8, fig. 4) and sixth 

 lumbars. The sixth (pi. 9, fig. 5) lacks the posterior epiphysis and 

 the eighth (pi. 9, fig. 4) lacks both epiphyses. The prezygapophj^ses 

 of both lumbars are damaged, but those of the eighth are the best 

 preserved. The right parapophysis, the posterior epiphysis, the 

 neural arch and its associated structures are missing on the tenth 

 lumbar (pi. 9, fig. 6). On the sixth and eighth lumbars the neural 



