90 Journal of Comparative Neurology and Psychology. 



segment, which is in the height of the lumbar enlargement, the 

 lateral diameter became i6 millimeters. The dorso-ventral diame- 

 ter, however, taken along the lateral wall of the sinus rhom- 

 boidalis and the fissura ventralis, was only 7 millimeters. 



From the caudal end of the first segment to the beginning 

 of the lumbar enlargement, the spinal cord of the of the emu 

 appears cylindrical or circular in section. With the lumbar en- 

 largement there begins a slight lateral flattening of its contour 

 which attains its height at the middle of the enlargement. The 

 conus medullaris is relatively much longer than in the mammal- 

 ian cord. At first the decrease from the enlargement is quite 

 sudden, then becomes more gradual, the conus being drawn 

 out to very slender proportions and comprising fully 10 seg- 

 ments, all of which are shorter than those cephalad to the lum- 

 bar region. 



In length the segments of the two extremities of the cord 

 were considerably shorter than those of the intervening portion, 

 gradually increasing in both directions but more rapidly from 

 the cephalic end. In the thoracic region they attaiaied a remark- 

 able length. The following are the lengths of some of the seg- 

 ments of one of the specimens obtained by measuring from the 

 center of attachment of one nerve pair to that of the next. 

 The measurements were made upon the formalin preserved ma- 

 terial. 



Streetek ('04 ) described segmental swellings in the lum- 

 bar enlargement of the ostrich and shows them occurring at the 

 level of the attachment of the ventral roots of this region. 



