264 MR. W. P. PYCRAFT ON THE MORPHOLOGY AND 
Stellung einnehmen,” and adds: “Ihre Vorgeschichte kommt mir am meisten dunkel 
By this time the tendency of the foregoing will no doubt have revealed itself. Its 
intention is to suggest that Dromeus and Casuarius—the Dromewide—are to be 
regarded as the most primitive of the Palwognathe; and that the Struthionide are 
most probably the nearest approach thereto, for, in spite of the great specialization 
which they have undergone, they undoubtedly retain many archaic characters. 
The Rheide, Dinornithide, Aypornithide, and Crypturi are all probably more 
nearly related one to another than to the Dromeide. The Apterygide are the most 
aberrant of all, but have affinities with the Dinornithide. 
This implies that the Paleognathe are to be regarded as polyphyletic—probably 
triphyietic. An attempt to express this relationship is given in the diagram on 
p- 265. 
I propose to discuss the details of this “tree” in so far as concerns the Neognathe 
elsewhere. Of the Palwognathe I need only say I recognize 7 Orders, viz. :— 
Casuarii. 
Struthiones. 
Rhee. 
Crypturi. 
Dinornithes. 
Epyornithes. 
Apteryges. e 
Their relation to the other members of the Class may be expressed as follows :— 
Class AVES. 
Subclass I. ArncHAORNITHES. 
» Ll. Nrornirues. 
Grade A. Palwognathe. 
» B. Neognathe. 
It would have been helpful here to discuss the further evolution of this group to its 
final end in the various genera and species, but this is unfortunately impossible in 
the present contribution owing to lack of material. The diagram will give a slight 
indication of the writer’s views on this subject. 
