( 387 ) 



been done the specific characters of the various species of this genus so far as 

 concerns their internal structure. 



In dealing with this subject, however, I am b}- no means breaking new ground. 

 A few osteological marks of difference between A. australis and .1. oweni have been 

 pointed out by Dr. Mivart, F.R.S.,* in his Memoir upon the axial skeleton of the 

 Struthionidae. More important as a contribution to the present question is a 

 memoir by Professor T. J. Parker, F.R.S., chiefly concerned with a description of 

 the development of this genus, but containing incidentally many and valuable notes 

 upon the specific characters of A. austmlis, A. oiveni, and A. nuintelli, besides a 

 few remarks upon the wing of A. haaati, upon its skeleton (doubtfully referred to 

 this species), and of A. maxima (probably "a sub-adult A. bulleri"). Professor 

 Parker had, however, fewer complete specimens of these birds than I have had the 

 privilege of examining. This, it is hardly necessary to point out, reduces the value 

 of the specific determinations based upon them ; and I shall have to point out later 

 the very considerable variations that occur in most parts of the skeletons of all the 

 species of the genus Apteryx, a fact which renders the tabulation of reliable specific 

 differences extremely difiScult. 



The general anatomy of Apteryx has been apparently so exhaustively treated 

 of (see the list of memoirs dealing with the genus) that I had hardly hoped to 

 discover any new points. I have, however, been able to ascertain two new facts 

 of some little classificatory importance. The first of these is the existence of an 

 oil gland hitherto overlooked, a feature in which this genus appears to differ from 

 all other Strnthious birds ; the second matter is the presence of definite intrinsic 

 syringeal muscles, not unique among the Struthiones, but new to Apteryx so 

 far as recorded fact enables me to judge. A few minor novel points are only of 

 systematic value. 



The memoirs which I have consulted in the preparation of this paper are 

 the following : — 



Parker, T. J. " Observations on the Anatomy and Development of Apteryx." 



PM. Trans. 1891. 

 Forbes, W. A. " On the . . . Trachea in the Ratite Birds." P.Z.S., 1881, p. 778. 

 Owen, Sir R. '' On the Apteryx australis." Trans. Z.S., ii. p. 57, and iii. p. 277. 

 MiVART, St. G. " On the Axial Skeleton of the Struthionidae." Trans. Z.S., 



X. p. 1. 

 FtJRBRiNGBR, M. " UntersuchuDgeu znr Morphologie nnd Systematik der Vogel." 



Amsterdam, 1888. 

 Gadow, H. " Aves " in " Bronn's Klassen und Ordnungen des Thierreichs." 

 Huxley, T. H. " On the Respiratory Organs of Apteryx." P.Z.S., 1882, p. 560. 

 MiTCHEtL, P. Chalmers. " On the Intestinal Tract of Birds." P.Z.S., 1896, 



p. 136. 

 Beddard, F. E. " On the Heart of Apteryx." P.Z.S., 1885, p. 188. 

 Lankester, E. R. " On the Heart described by Professor Owen in 1841 as that of 



Apteryx." P.Z.S., 1885, p. 239. 

 Lankester, E. R. " On the Right Cardiac Valve of the Specimens of Apteryx 



dissected by Sir Richard Owen in 1841." P.Z.S., 1885, p. 477. 

 Owen, Sir R. " On the Structure of the Heart in Ornithorynchus and Apteryx.'' 



P.Z.S., 1885, p. 328. 



♦ See list of literature above. 



