400 PROCESSOR OWEN ON THE GENUS CNEMIORNIS. 



surface, slightly projects towards the back (anconal) side of the bone, where it is 

 divided by a groove from the articular head, but there is no excavation below it for a 

 pneumatic foramen. The outer (radial) tuberosity (b) is almost obsolete, being repre- 

 sented by the short, thickish ridge continued from the outer end of the head downward 

 and a little forward, with a deepish cavity behind. The pectoral ridge, instead of 

 being continued directly from the tuberosity, as in birds of flight, is represented by a 

 tubercle (6'). an inch below this part. There is a shallow, transverse depression (d) 

 below the head on the palmar side, and a subsemicircular, slightly concave, smooth 

 surface below that depression. The shaft of the humerus is slightly bent forward ; it 

 is subcircular, a little expanded and flattened at the distal end. This shows, feebly 

 developed, the ulnar articular convexity (/), and the longer, narrower, and more 

 prominent radial one (e) ; there is a slight ento-condyloid tuberosity (h), and a very 

 feebly indicated, transversely concave, anconal depression. 



Femur. 



The femur (PL LXV. figs. 1 & 2), about the size of that of Dinornis gerano'ides 

 (ib. figs. 5 & 6), differs in being more compressed from behind forward, especially at the 

 proximal end. The head is more sessile ; the depression for the round ligament is deeper 

 and larger, and is on the upper part (tig. 2, a). The articular ' epitrochanterian' surface (6), 

 extended from it to the great trochanter, is more horizontal ; that process (c) being less 

 elevated, and forming a more abrupt ridge at the outer boundary of the articular 

 surface. There is a low trochanter minor {d), for the iliacus internus, about 9 lines 

 below the head, in the femur of Cnemiornis, of which no trace appears in that of 

 Dinornis gerano'ides (fig. 5). The shaft has an oval, transverse section, with the small 

 end acute, formed by the inner side or border of the shaft : the posterior ridge is nearer 

 this border than in Dinornis gerano'ides. The outer condyle (e) extends lower than the 

 inner one (/) to a degree greater than in Dinornis. The rotular fossa (p), and that for 

 the head of the tibia, are deeper than in Dinornis. There is no pneumatic foramen. 

 The canal for the medullary artery is very small, and perforates the back of the shaft, 

 in one specimen, above the middle. There is a curved, rough ridge above and behind 

 the outer condyle, but not the fossa which impresses this part above the vertical groove 

 for the fibula in Dinornis gerano'ides and most other species of Dinornis^. 



As compared with that oi Aptornis (figs. 3 & 4), the femur of Cnemiornis is much 

 thicker in proportion to its length, but resembles it in the ridged character of the 

 trochanter major, in the high position of the depression for the ligamentum teres, 

 which, however, is more posterior in Aptornis (fig. 4, a), in the more compressed cha- 

 racter of the upper part of the bone, and in the approximation of the posterior ridge to 

 the inner side of the shaft ; but that ridge is interrupted an inch above the inner 

 condyle in Cnemiornis, and is continued sharply to it in Aptornis, in which also the 



' Zool. Trans, vol. It. p. 142. 



