456 SYSTEM A TIC SYNOPSIS. — PICARI^ — CYPSELJFORMES. 



widening behind, its posterior margin entire; furculnm stout, rather U- than V-shaped. Oil- 

 gland nude. No coeca. Leg-muscles auomalogonatous (p. 195) ; femoro-caudal present, but 

 accessory femoro-caudal, semiteudinosus, accessory semitendinosus and anibieus absent. Eggs 

 several, narrowly oval, white. 



" One of tlie most remarkable points in the structure of the Cypselidcc is the great devel- 

 opment of the salivary glands. In all the species of which the uidification is known, the 

 secretion thus produced is used more or less in the construction of the nest. In most cases it 

 f >rms a glue by which the other materials are joined together, and the whole nest is affixed to a 

 rock, wall, or other object against which it is jilaced. In some species of CoHocalia, however, 

 the whole nest is made up of inspissated saliva, and becomes the ' edible bird's nest ' so well 

 known in the East." (Sclater.) 



A well-defined family of G or S genera and about 50 species, inhabiting temperate and warm 

 parts of the globe. They are rather small birds, of plain plumage, closely resembling swallows 

 iu superficial respects, but with no real affinity to these Oscines. Notwithstanding the utmost 

 difierence in the shape of the bill, the real affinities are witli the tenuirostral TrochilidcB in 

 every structural peculiarity. They are birds of extraordinary volitorial ability, being only sur- 

 passed in this respect by the hummers themselves. The family is divisible into two subfami- 

 lies, according to the structure of the feet. 



Analysis of Subfamilies and Genera. 

 Cypselin^. Front toes with 3 joints apiece. Hind toe lateral or versatile. Tarsi feathered. 



Toes feathered. Tail not spiny Panyptila 131 



CH.ff:TUBiN^. Front toes with 3, 4, and 5 joints from Inner to outer. Hind toe posterior or lateral, but 

 not reversed. Tarsi and toes naked. 



Tail emarginate, not mucronate Nephmcetes 132 



Tail rounded, mucronate Chatura 133 



31. Subfamily CYPSELIN/E: Typical Swifts. 



Ratio of the phalanges abnormal, tbe 3d and 4th toes having each 3 joints like the 2d ; 

 basal phalanges of all the anterior toes very short (fig. 40). Hind toe reversed (in Cypselus, 

 where nearly aU the species belong), or lateral (iu Panyptila). Tarsi feathered (in Cyi^selus) ; 

 toes also feathered (in Panyptila). Contains only these two genera and nearly half the species 

 of the family. Of Panyptila there are only three well-determined species, all American ; while 

 Cypselus has upward of twenty, mostly of the Old World ; the three or four American ones 

 being sometimes detached under the name of Tachornis. 



131, PANY'PTILA. (Gr. ttcivv, panu, much, very; irriXov, ptilon, wiug : iu allusion to the length 

 of wing.) Rock Swifts. Tail about i as long as wing, forked, with stiffish and narrowed, 

 but not spiny feathers. Wing pointed by the 2d primary, the I'st decidedly shorter. Tarsi 

 feathered to the toes ; these also feathered to some extent. Hind toe elevated, lateral, but not 

 reversible. Front toes with slight basal webs. Eyelids naked. Colors black and white. 



403. P. saxa'tilis. (Lat. saxatilis, rock -inhabiting ; saxum, a rock.) White-throated Rock 

 Swift. Black or blackish ; chin, throat, breast, and middle line of belly, tips of secondaries, 

 edge of outer primary and lateral tail-feathers, and a flank-patch, white. Forehead and line 

 ■ over eye pale ; a velvety black space before eye. Bill black ; feet drying yellowish. The 

 purity of the color varies with the wear of the feathers, some specimens being dull sooty 

 brownish, others more purely and even glossy blackish. The extent of the white along the 

 belly is very variable. The flank-patches are conspicuous, in life sometimes almost meeting 

 over the rump. Length 6.50-7.00 ; extent about 14.00 : wing the same as total length ; tail 

 about 2.66, forked, soft-. Southwestern U. S. and southward, breeding in colonies on clifis ; a 

 large and beautiful smft — a high-flier of almost incredible velocity, with a loud shrill twitter, 

 nesting in the most inaccessible places, sometimes by thousands. The eggs do not appear to 

 have been taken yet, but are presumed to be white, as in aU the species the eggs of which are 

 known. Found N. to Wyoming, Utah, and Nevada. 



