Gallino-Gralline Group of Birds. 433 



the articulation of the dorsal vertebrae precedence over the 

 bifurcation of the nasals. It is equally probable that the 

 reverse is the proper course. If it were carried out the 

 result would be that the Gruidse would be transferred from 

 the Grallae to the Gavise, whilst the genera (Edicnemus and 

 Pluvianus would be transferred from the Gavise to the Grallse. 

 It seems impossible to determine whether the Stone Curlews 

 ought to be removed from the society of the Coursers, and 

 from the anomalous position of being holorhinal birds be- 

 tween the Gulls and the Plovers, both of which are schizo- 

 rhinal, and be placed under the protection of the Bustards, 

 where they would be in the anomalous position of being opis- 

 thocoelous birds between the Bustards and the Trumpeters, 

 both of which are heterocoelous. 



COLYMBO-PODICIPES. 



It is with profound regret that I confess myself unable to 

 place the Divers in a different suborder from the Grebes. 

 In spite of the difference in their habits and the contrast 

 between their eggs, the osteological differences between the 

 Colyrabi and the Podicipes^ like those between the Gaviae 

 and the Limicolse, appear to be of only secondary importance. 

 On the other hand, the Alcidae, which are associated by many 

 systematists with the Colymbi and the Podicipes, present 

 many and important osteological differences. An opinion 

 based upon osteological characters alone must be regarded 

 with caution ; but osteology appears to teach that the Auks 

 are archaic Gulls, whilst the Grebes and the Divers are 

 highly specialized Penguins. 



The Colymbi differ from the Podicipes both in the 

 sternum and in the vertebrae. In the Colymbi all the ver- 

 tebrae in front of the ankylosed sacral vertebrae are free. In 

 the Podicipes the ankylosed sacral vertebrae are preceded 

 by only one free vertebra, in front of which are four anky- 

 losed dorsal vertebrae. In the Colymbi the median xiphoid 

 process of the sternum is prolonged until it projects beyond 

 the lateral processes, whilst in the Podicipes it is abruptly 



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