posterior diameter, and do not present lateral angles. They are composed 

 of not very dense osseous tissue. The anterior zygapophyses are rather 

 elongate, and their articular faces are directed steeply inwards. They are 

 rceived by corresponding shallow excavations, one on each side of the pos- 

 terior base of the neural spine. The neural spines are compressed and 

 straight, and become very robust towards the apex. 



The femur is extraordinarily robust. The great trochanter is low, but 

 the shaft is widest where it expands outward. The third trochanter is above 

 the middle, and is short and little prominent. It is on the inner edge of 

 the posterior aspect of the shaft, and looks backwards and inwards. The 

 shaft in its present state is compressed so as to reduce the antero-posterior 

 diameter. It is not however crushed or cracked. The condyles have 

 much greater transverse than antero- posterior extent. They are moderate- 

 ly produced backward, and are separated by a deep inter-condylar groove, 

 while the anterior trochlear groove is wide and well marked. The inner con- 

 dyle is narrowed posteriorly while the external one is obtuse and robust. 

 The articular extremity is marked with irregular pits as in Dystrophins and 

 Cetiosuurus. 



Measurements. 



M. 

 / fore and aft.. . .150 



Diameter of anterior caudal vertebra. 1 vertical 200 



' transverse 260 



Elevation to zygapophyses of the same 250 



Total elevation of the same 480 



Length of femur 1.400 



Proximal diameter of femur j fore and aft 105 



I transverse 410 



Distal diameter of femur { foreaDd aft 360 



I transverse 450 



Diameter of middle of shaft of femur 280 



The caudal vertebrae of this species are much more deeply bi-concave 

 than those of the Camarasaurus supremus ; they also differ in their rela- 

 tively and absolutely greater breadth of centrum. 



Published December 10, 1877 



