304 PROF. HUXLEY ON THE ALECTOROMORPHiE. [May 14, 



his great work "On the Shoulder-girdle and Sternum" (p. 187). 

 Thus the sternum of Hemipodius is strongly Tinamine. 



4. The furcula is peculiar, but has been compared by Mr. Parker 

 to that of the Lapwings. The coracoid has a subclavicular pro- 

 cesss, as in Pteroclomorphce, Peristeromorphce, and Charadriomor- 

 phcB. This process does not exist in Tinamus. 



5. The pelvis in some respects resembles that of Syrrhaptes, in 

 others that of the Plovers, but has peculiarities of its own. In no 

 respect is it Alectoromorphic. 



6. The tarso-metatarsus is quite Pteroclomorphic. Mr. Parker 

 thinks Hemipodius to be intermediate between Pterocles and Syr- 

 rhaptes in this part of its organization. 



The same writer has already pointed out the osteological affinities 

 of Hemipodius to the Plovers on the one hand, and to Tinamus on the 

 other. In his memoir on the sternum and shoulder-girdle (p. 185) 

 he goes so far as to say that " the Hemipodine family is interposed 

 bodily between the Tinamous and the true Galiinse." 



I think that this is a very just estimate of the position of the 

 group, if the Pteroclomorphce are included under the head of Gcdlince. 

 For it is obvious that the chief relations of Hemipodius are on one 

 side with Tinamus, on another with Syrrhaptes, and on a third with 

 the Plovers, Pedionomus being perhaps the connecting link between 

 the "latter and it. 



But it appears to me impossible to include Hemipodius with either 

 the Tinamorphce or the Charadriomorphte, and still less with the 

 Pteroclomorphce ; and I see no alternative but to make it the type 

 of an independent group, which may be called the Turnicimorphce. 



III. The affinities of O^hthocomvi?,. 



Many of the peculiarities of Opisthocomus have already been de- 

 scribed and discussed by L'Herminier*, Devillef, and Gervais:^ ; 

 and the latter author has given a figure of the skeleton. 



L'Herminier is of opinion that the sum of the characters of the 

 bird incline it towards the GallinacecB. He puts it, with Vicillot and 

 Latreille, in the distinct family of the Dysodes, before the Pigeons 

 and Gallinaceous birds. 



M. Gervais (/. c. p. 72), on the contrary, denies that Ojjisthoco- 

 mus has anything to do either with the Gallinaceous birds or with 

 the Pigeons. He considers that it forms part of the great series of 

 "passeriform birds," but is so different from the others that it 

 ought to form a separate order in this series, near the Scatisores, 

 and " near the MusophagidcB, though its affinities with the group 

 may have been exaggerated." 



* Recherches Anatomiques sur quelques genres d'Oiseaux rares (Comptes 

 Rendus, v. 18,37, p. 433). 



t Observations fails en Amerique (Revue et Magasin de Zoologie, ser. 2. t. iv. 

 1852). 



X Castelnau, Expedition dans les parties centrales dc 1' Amerique du Sud, 7""^ 

 partie, Zoologie. 



A 



