MICR OPODIDjE : S WIFTS. 



555 



Suborder CYPSELI: Swifts. 



See p. 540 for characters of this compact monotypic group, 

 which consists of a single family, unless the peculiarities of the 

 genus Macropteryx (<jr Dendrochelidon) be evaluated at the rank 

 of another family. There is no question of the proper position 

 oi Cypseli ; fur, notwithstanding the obvious difference between 

 an extremely fissirostral and an extremely tenuirostral type of 

 bill, the Swifts are such very near relatives of the Humming- 

 birds, that the two might be combined in one suborder Macro- 

 chires. The skeletal and muscular cliaracters most useful in 

 classification are quite alike. Thus, there is a similar con- 

 formation of the palate; the same deep-keeled sternum, and 

 the same relative proportions of the upper arm, fore-arm, 

 and manus; but tlie Swifts have a less perfectly pas- 

 serine foot than the Hummingbirds, sometimes with 

 a different ratio of the phalanges, or reversed position 

 of the iuillux. The myological formula i-? identic<il, 

 in the absence of the accessory fcmorocaudal, sem- 

 itendinosus, and accessory semitendinous, as u(ll 

 as of the ambiens; and there is the same pecuh- 

 arity of the tensor patagii brevis. In both sub- 

 orders there are no cfcca, though the oil-irland 

 is nude; and in Cypseli the seven secondauch 

 are but one more than the minimum numb( i 

 found in the Hummers. Other features of th( 

 Ci/pxeli will be jxiinted out under the head ot 

 tlie only establislied family, commonly called 

 Cypseliche, but now known as Micropodidcc 

 Furthermore it need only be remarked hen 

 close supei-ficial resemblance between Swifts 

 simply mimetic; and it is not necessarj 

 trust also not required by the reader 

 "Key" thus far) to argue the differ- 

 Oscine Passerine and any Picarian 



it the >tiikingly 

 ,ind Sw.illows is 

 at this late day (I 

 who has turned the 

 ences between an 

 bird. 



Family MICROPODID^ 



Swifts. 



{Cypselidce of former edd. 

 of tlie Key.) 



Fissirostral macrochiroi<< 

 angular when viewed from 

 eyes, unnotched, unbris- 

 Nostrils exposed, superior, 

 feathers tending to reach 

 loiii,', tiiin, and jiointed (frequently as lonir as the whtde bird); primaries acute and somewhat 

 falcate; secondaries extremely short and few. 'J'ail of 10 rectrices, variable in shape, often 

 mucronute. Feet small, weak, the cnvehip rather skinny than scaly; tarsi naked or teathered; 



Fio. 374. — White-throated Swift, nat. size. 

 (E. H. Fitch.) 



I'icaricc: Bill very small, flattened, tri- 

 above, with great gape reaching below 

 tied, about six times as long as ctilmen. 

 nearer ciilmcn than commissure; frontal 

 forward under them. Wings extremely 



