COLUMBA 



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different from that of any animal so far described. The 

 acetabulum is perforated, and is formed from the usual three 

 bones, ilium, ischium, and pubis. The ilium extends forwards 



and backwards and is attached to the long sacrum. The 

 ischium is fused along the greater part of its length with the 

 posterior part of the ilium, leaving an ilio-sciatic foramen 



