30 



MEMOIES OF THE CARNEGIE MUSEUM 



pophysial lamina which abuts against and gives sujDport to the anterior end of the 

 ihum and sends off a rather delicate inferior branch which comes in contact with 

 the lower border of the anterior blade of the ilium at its junction with the pubic 

 peduncle. There is a large foramen between these two branches of the inferior dia- 

 pophysial lamina and another and larger between the diapophyses and the inferior 

 margin of the diapophysial lamina. There is a third and smaller foramen in the 

 diapophysial lamina near its union with the neural arch. In addition to these fora- 

 mina the cavity enclosed between the diapophysial laminae of this and the first 

 sacral is left widely open both superiorly and inferiorly. The centrum is broad and 



FiCt. 9. Inferior view of sacrum and ilia of Dlplodocus carnegii (No. 94), one tenth natural size ; pb, 

 pubic peduncle ; is, ischiac peduncle ; a, anterior end ; p, posterior end. 



short with pleuro-central cavity simple and of moderate depth. The zygapophyses 

 are small and short. The articular surfaces are less extended than in any of the 

 preceding dorsals. The neural spine is simple, very strong, and transversely ex- 

 panded and rugose at the summit. There are exceedingly strong and rugose pre- 

 spinal and postspinal laminse. The superior blades of the diapophysial laminae are 

 well developed and have prominent superior rugosities. There was a small ossicle 

 found between the spine of this vertebi'a and that of the first sacral. It is shown in 

 position in the restoration. 



The Sclerals. — The sacrum in Diplodocus may be regarded as composed of either 



