266 MR. W. P. PYCRAFT ON THE MORPHOLOGY AND 



SUMMARY. 



The group of birds which we collectively designate the " Ratitse " is the same as that 

 to which this name was originally given' by Merrem in 1813 (with the addition of 

 Apteryx, then unknown), on account of the fact that all agreed in the absence of a keel 

 to the sternum. They were "raft-breasted," in contradistinction to the Carinatse, or 

 keel-breasted 1 . 



Nitzsch, Huxley, Newton, Sclater, and Sharpe have successively adopted Merrem's 

 subdivision of the class Aves — adding the Saururse, unknown to Merrem. 



Other workers, both before and since Merrem, have accorded to the " Ratitse " no 

 greater prominence than that of an order or suborder of the class Aves. Sometimes 

 even this was considered too great a distinction, and they were reduced to the rank of 

 a Family, including such forms as Bustards, Plovers, &c. 



The " Ratitse " of Merrem were apparently regarded by that author, as well as by 

 Huxley, Newton, Sclater, Sharpe, and other systematists, as a monophyletic group. 

 Furbringer, Gadow, and Parker stand prominently forward as advocates for a poly- 

 phyletic origin. 



Gadow's views are admirably set forth in his contribution to Bronn's ' Thier- Reich ' 

 [26]. Briefly, he regards the " Ratitse " as a morphologically monophyletic group, 

 standing in the same relation to the class Aves as the Anthropomorphic to the rest of 

 the Mammalia. 



With this view we entirely agree. We venture further, and include the Crypturi 

 within the group. This was done long since by Garrod [30] and Stejneger. 

 Beddard [7], later, has shown a strong inclination to follow suit. Thus, he says : — " It 

 is unquestionably to the Struthiones that they showed the greatest number of important 

 likenesses, so much so, indeed, that their inclusion in one great group with them 

 would be by no means an unreasonable way of disposing of them." 



The Dromseognathous palate is sufficient justification for such an association. 

 Consent to this, however, renders inoperative the old term " Ratitse," which at best is 

 but a makeshift ; for many of the Carinatse are Ratite, whilst the Tmamous have a 

 large keel to the sternum. 



We propose instead the terms Palceognathce (Ratitae + Crypturi) and Neognathce 

 (Carinatse — Crypturi). The adoption of these surmounts the difficulty indicated above. 



Gadow regards the Struthiones as a group of primitive forms more nearly repre- 

 senting Proto-Carinatse than any other living birds. Their retention under the common 

 name " Ratitse " he regarded as convenient rather than an indication of close affinity. 



Similarly we regard the Palceognathce as the unsuccessful descendants of proto- 

 carinate forms, but retaining probably but few of their characteristics unaltered. It 

 would be too much to regard any of the existing Neognathce as the direct descendants 

 of any of the existing or extinct Palceognathce known to us, but it seems not 



1 Blanehard in 1859 substituted for Merrem's the terms Tropido- and Homalosterni. 



