254 



Transaction. — Zoology. 



posterior articular surface of the mass is nearly circular, and 3 inches in 

 diameter. 



The first dorsal has the neural arch incomplete, but all the other vertebrae in 

 the middle of the column have their expanded processes largely developed. 



The cervical mass has six lateral foramina and seven overlapping laminae in 

 the united neural spine, for which reason I conclude it consists of seven 

 vertebral segments. Following this, the first dorsal is very feebly developed, 

 with the neural arch open above and short styliform lateral processes. The 

 second has a complete neural arch, but the spine is low. The lateral process 

 is also short and slender, and like the first has no costal facet. 



The third to thirteenth dorsals have articular indentations on the broad 

 outer margin of the lateral processes, but these become gradually indistinct. 

 This agrees with the character of the vertebral end of the ribs, those belonging 

 to the fourteenth, fifteenth, sixteenth, and seventeenth dorsal segments 

 tapering as if they had only a ligamentous attachment along their posterior 

 border. This agrees with Mr. Traill's remark that the hinder ribs were set at 

 a remarkably acute angle backwards on the vertebrae. 



The transverse processes of all the vertebrae behind the second dorsal 

 are greatly expanded and very thin ; thus, that of the eleventh dorsal is 5.5 

 inches wide by 6*5 inches long, the neck of the process which springs from 

 the vertebrae being only 3 inches, and the thickness of the blade of the process 

 only J inch. They occupy nearly the same place throughout in relation to 

 the bodies of the vertebrae. 



The neural spines are at first directed forwards, but at the sixth dorsal 

 begin to slope backwards and soon become very oblique. The centra also 

 rapidly increase in length, that of the twenty-eighth beiug the longest. The 

 measurements of the centra, taken without the epiphysial disks, are as 

 follows : — 



Verte 



bree. 











In. 



Vertebrae. 







In. 



1-7. 



Cervical i 



mass 





... 



... 30 



2G. 



2nd lumbar 



... 4G 



8. 



1st dorsal ... 





• • • 



•8 



27. 



3rd 



9 9 



... 



... 4-7 



9. 



2n(l 



>> 



■ • • 







•9 



28, 



4th 



9 9 



... 



... 4-8 



10. 



3r(l 



>> 



(first 



with 



a rib) 



... 1-2 



29. 



1st caudal 



(with chevron) 



... 4-5 



11. 



4th 



>> 









... 1-6 



30. 



2ud 



}i 



• ■ • • • • 



... 4-2 



12. 



5th 



)> 









... 20 



31. 



3rd 



;> 



... ■ • 



... 40 



13. 



Cth 



5> 









... 2-3 



32. 



4th 



; y 



• • • • . • 



... 3-5 



14. 



7th 



>) 









... 2-6 



33. 



5th 



)> 



... 



... 3-3 



15. 



8th 



>> 









... 2-9 



34. 



()th 



>> 



(last neural spine) 



... 2-8 



16. 



9th 



>> 









.. 3-2 



35. 



7tli 



>i 



... 



... 1-8 



17. 



10th 



)> 









... 3-3 



3G. 



8th 



>> 



• > • . • I 



... 1-5 



18. 



11th 



>> 









... 3-5 



37. 



9th 



>) 



• • • • • • 



... 1-4 



19. 



12th 



) ) 









... 36 



.38. 



10th 



> > 



... 



... 11 



20. 



13th 



> > 









... 30 



39. 



11th 



) > 



... 



... 10 



21. 



14th 



)> 









... 3-9 



40. 



r2th 



M 



... 



... -8 



22. 



15th 



»» 









... 40 



41. 



13th 





... • . > 



wanting 



23. 



IGth 



>> 









... 41 



42. 



14th 





... 



y 1 



24. 



17th 



> » 



(last 



rib) 





... 4-3 



43. 



15th 



M 



... 



... G 



25. 



lut lumbar 







.. 4-5 



44. 



IGth 



M 



... 



•3 



