PROFESSOR OWEN ON THE GENUS DINORNIS. 253 



of the femur, the greater robustness of the bone in this the least robust of the genus, 

 the much higher trochanter, the much wider distal extremity, and especially the wider 

 and shallower cavity for the patella. From the equality of size of this femur with that 

 of the Emeu, the species which it indicates may be termed Dinornis dromceoides. v 



Pelvis. (Plates XIX. XX. & XX a.) 



The first portion of the pelvis here described consists of twelve anterior anchylosed 

 vertebra; of the sacrum, with a portion of the right ilium and acetabulum (PI. XIX. 

 fig. I.). Of the size of this fiine fragment an idea will be given by the subjoined table of 

 its dimensions, compared with those in a full-sized Ostrich. 



Dinornis, p 1. Struthio. 

 In. Lin. In. Lin. 



Height of the first sacral vertebra 610 46 



Breadth of the articular surface of the body of ditto ..34 18 



Breadth of the seventh sacral vertebra 3 3 13 



Length of the first seven sacral vertebrae 6 6 6 9 



The last admeasurement shows that the anterior part of the sacrum, including the 

 first series of vertebrae provided with double transvei'se processes on each side', is 

 shorter in proportion to its height and breadth compared with the Ostrich ; and these 

 j)roportions are shown to characterize the entire pelvis by the smaller specimen, subse- 

 quently to be described. The under surfaces of the first seven vertebree are flattened, 

 and form a smooth and slightly concave platform in the remaining four. The inferior 

 transverse processes pass out horizontally to the lower border of the ilium, which de- 

 scends to the level of the under surface of the bodies of the sacral vertebrae. In the 

 Ostrich they ascend obliquely upwards to join the upper transverse processes, before 

 abutting against the lower border of the ilium, which does not descend so low as the 

 bodies of the vertebrae. 



In the Ostrich the first two inferior transverse processes of the sacrum retain their 

 primitive condition of detached ribs, and three transverse processes succeed them before 

 the commencement of the os pubis. In the great Dinornis the second sacral rib is an- 

 chylosed as a transverse process, and four other processes succeed this before the one 

 which abuts against the beginning of the pubis : this is much thicker and stronger than 

 the preceding ones, and it is succeeded by four confluent sacral vertebrae, which have no 

 lower transverse processes. In the Ostrich the transverse processes of the sixth sacral 

 vertebra abut against the part of the innominatum from which the pubis is continued, 

 and the transverse processes of the four succeeding vertebrae abut against the origin of 

 the ischium, parallel with the lower part of the acetabulum ; then a single vertebra with- 

 out a lower transverse process or sacral rib intervenes before these are again developed, 

 to abut against the posterior part of the acetabulum. 



' See description of the sacrum in Birds, in the ' Cyclopaedia of Anatomy,' art. Aves, p. 271, 



2l2 



