Haast. — On the Extinct Genus Harpagornis. 69 



Harpagornis assijnilis. 



Inches. 

 Total length ... ... ... ... ... 5-87 



Circumference at its proximal end, ridges included ... 3 "78 

 Circumference at its distal end ... ... ... 4-02 



Circumference of shaft where thinnest ... ... 1-78 



The shaft of this bone, if we compare its total length with that of //. onoorei, 

 is generally narrower ; this is most conspicuous above the deeply excavated 

 process for the attachment of the back-toe metatarsal, where the shaft is 

 thinnest. 



The ectocondylar ridge is also more pi'onounced, by which the shaft 

 assumes a more triangular form than it possesses in the larger species. The 

 two posterior ridges on both sides of the concave channel are more sharply 

 defined, so that the latter is deeper than in H. moorei, approaching in form 

 more that of the Australian Eagle. 



Humerus. 

 Harpagornis moorei. 



I already observed, in the preliminary remarks, that our search in the 

 turbary deposits of Glenmark after the humerus of this species had been 

 unsuccessful, but that we obtained a fragment of that bone from the 

 postpliocene alluvium on the banks of the Glenmark Creek, about one mile 

 above Glenmark. This fragment consists of the greater portion of the shaft, 

 the proximal and distal extremities being broken off. 



The shaft where thinnest has a circumference of 2'20 inches, or 0"lo inch 

 more than the same bone of Harpagornis assimilis, of which we possess a 

 perfect specimen. 



It doubtless belonged to an adult bird, and, if restored, would be about an 

 inch longer than the smaller species. 



Harpagornis assimilis. PI. VIII., Figs. 1 and 2. 



Inches, 

 8-57 

 4-49 



Total length 



Circumference of proximal end 



Circumference of distal end ... ... ... 4*10 



Circumference of shaft where thinnest ... ... 2-05 



This important bone, with the exception of a small portion of the radial 

 crest, is quite perfect. In its general outlines it has, like the other portions 

 of the skeleton, great affinities both to Aquila and Circus. 



The shaft is not so straight as that of Aquila, having below the lower 

 termination of the radial crest an outward bend, which is also well exhibited 

 in Circus. At the same time, the proximal extremity is more curved towards 

 the ulnar side in the fossil bone. 



