174 PKOFESSOE OWEN ON THE GENUS DINOENIS. 



Dr. von Haast has followed his ornithological countryman's procedure in a further 

 generic subdivision of the Binornithidce^. 



Dinornis didiformis — the type of Eeichenhach's genus Anomalopteryx (1850) — is the 

 type of Von Haast's genus Meiornis (1874). The Eurapteryx of Von Haast (1874) 

 is the Syornis of Reichenbach (1850), both represented by Dinornis casuarinus. 



My Dinornis cicrtus is the type of Eeichenhach's genus Cela : his genus Movia has 

 Dinornis ingens for the type. The old generic term Dinornis is restricted by Reichen- 

 bach to the species D. sfruthioides ; audi), giganteus is referred to a genus ilfoa (1850). 



These generifications of the accomplished author of the ' Handbuch der speciellen 

 Ornithologie ' have not met with acceptance or favour at the hands of subsequent 

 systematists. Whether the parallel labours of Dr. von Haast will be more fortunate 

 remains to be seen. 



Returning to my more congenial task of Comparative Anatomy, if Plate XXXII. 

 or the reduced outlines of the sternum in species of Dinornis (cut, fig. 35) be compared 

 with the figures of the sternum of Strut/do in Mivart's figs. 77-79, the straightness of 

 the anterior border and the smallness of the contiguous coracoid grooves (b, b' in Plate 

 XXXII.) contrast with the undulate contour of the same border and the length of those 

 grooves (c, c) in Struthio, vihich almost meet at the mid line. The body of the breast- 

 bone is more convex and bulging in the Ostrich ; the lateral processes (called ' xiphoid,' 

 and marked Ix by Mivart) are absolutely and relatively much shorter; the medial 

 posterior processes, which seem to me more analogous to the mammalian ' xiphoid ' 

 (Plate XXXII. g, g), are wanting in Struthio ; and instead of the mid notch (ib. n), 

 there is, in Struthio, an obtuse production. 



The costal border shows differences, as in longitudinal extent, in accordance with the 

 greater number of sternal ribs to which it gives attachment in Struthio ; this border 

 differs also in breadth and in the complexity of the articular surfaces, corresponding, in 

 Struthio, to the more expanded and subbifid sternal ends of five of the six pairs of 

 sternal ribs which articulate therewith in that existing form. 



The sternum of Apteryx conforms much more closely to the type of that bone in 

 Dinornis than does the sternum in any other known species of bird. Modification has 

 reigned in the peripheral prehensile portion of the cephalic extremity of the vertebral 

 column. 



To the side view ^ of " the sacral and caudal vertebrae of a young Ostrich " ^ Prof. 

 Mivart •* has added a haemal (' ventral ' or lower) view (fig. 60, loc. cit.) and a neural 



' " Address to the Philosophical Institute of Canterhiuy," in the ' Lyttelton Times ' of Friday, March 6th, 

 1874; reprinted in the ' Transactions of the New-Zealand Institute,' vol. vi. June 187-1, p. 419. 



- ' Archetype and Homologies of the Vertebrate Skeleton,' 8vo, 1848, p. 159, fig. 27. 



' ' Descriptive Catalogue of the Oateological Series contained in the Museum of the Royal College of Surgeons 

 of England,' 4to, 1853, p. 266, no. 1885. 



* " The Museum of the College of Surgeons fortunately possesses a preparation of the sacral vertebrae (figs. 

 58, 59, 60, and 61) of a young Ostrich in an nnanchylosed condition, which enables the serial description of 



