MACEOCHIKES 



229 



Nu 



observer is disinclined to allow a very near affinity between 

 the birds, it is undeniable that there are resemblances. 



The skull is schizognathous in the humming bird, 

 aegithognathous in the swifts. But the aegithognathism in 

 the latter is a little abnormal. GARROD has pointed out in 

 describing ' the osteology of Indicator that that bird, in 

 common with the CapitonidEe, has a truncated vomer, in 

 which the truncation occurs behind the line joining the 

 maxillo-palatines, while . in the true 

 Passeres the truncation is in front of 

 this line. The swifts are intermediate, 

 the truncation being, as is shown in 

 the accompanying figure (fig. 104), 

 about on a level with the line joining 

 the maxillo-palatines. It is true that 

 the lateral processes so characteristic 

 of the aagithognathous skull are better 

 developed in the swifts than in the 

 swallows ; but, on the other hand, it 

 must be borne in mind that the un- 

 doubtedly a3githognathous Indicator 

 is without these processes. In both 



swifts and humming birds the skull is 7 , i( . s ieian<>iciicii*. UNDER 

 holorhinal and without basipterygoid VlEW - < AFTER SHUFELDT.) 



/'in.r, preiuaxiila ; M.rp. maxillo- 



DrOCeSSeS. AS tO the VOmer, palatines: Vo, vomer: .V, 



nasal ; /V, palatine ; /Y, ptery- 



HUXLEY described it as truncated ; .goi.i. 



but SHUFELDT finds it to end in an 



excessively fine point. In swifts the vomer is, as already 



stated, truncated. But as to this difference and its value as 



a means of separating the birds cf. the manifold vomer of 



Limicolae. 



The humming birds have fourteen or fifteen (Trochilus 

 Alexandra) cervical vertebra. The Cypselidse have thirteen 

 or fourteen. Four ribs 2 join the sternum on each side 



gidas, and Cypselidse,' P. Z. S. 1885, p. 880, and 1886, p. 501. See also ZEHNTNEK, 

 ' Beitriige z. Entwicklung von Cypsdus mclba,' Arch. f. Naturg. Ivi. 1S90, p. 189 

 (transl. in Ibis, 1890, p. 196). 



1 Loc. cit. (on p. 196.) - Fri;i;i;i\<iEH says five or six. 



FIG. 104. SKULL OF Micro- 



