150 



Gekus GAMPSONYX, Vigoes. 



Gampso))i/x Vigors, Zool. Jonrn. ii, 1325, p. 69. Type, G. swainsoni Yig. 

 Chondrohierax Less, (fide Sharpe, Cat. Ace. Brit. Mas. 1874, 340). 



Ch. — Similar to Ukavus, but mucli smaller, and differiug- iu relative 

 proportions of different parts. Colors more varied. Tail more than 

 two-tbirds as long as tbe wing; scales of the feet larger, tbe upper 

 surface of tbe toes baviiig transverse scutellie to their bases. 



This genus is very closely related to Elaniis^ so much so in fact that 

 it may be questioned whether it is not merely subgeuerically distinct, 

 since they have so many features in comraou. These two genera also 

 agree with the genns Nauclerus of Africa in so many points in whicb all 

 three differ from other Falconidce that they seem to form a very well- 

 defined group, which may be termed the Ulani, and which may be char- 

 acterized by the following peculiar features common to the three genera. 



Group Elain'I. 



Ch. — Claws not grooved beneath, their under surface being merely 

 flattened, or even rounded.* Two, or none, of the outer quills with 

 their inner webs sinuated.t Tarsus without any transverse scutellfe, being 

 covered nearly uniformly with small rouudish or hexagonal scales. 

 Outer toe appreciably shorter than the inner {(in. in J^aucleriisf). 

 Kostril broadly ovate, nearly horizontal, situated in the middle of the 

 cere. 



The three genera differ from each other as follows : — 



A. Tomia without indentations. Tarsus about equal to, or just appre 



. ciably longer than, the middle toe; second or third quill longest 

 outer two with inner webs sinuated near their end. Tail much 

 shorter than the wing, double rounded. 



a. Tail less than two-thirds the wing. Scales of the feet very minute, 

 there being transverse scutellaj only on the terminal phalanx of 

 the toes Elanus. 



h. Tail more than two-thirds the wing. Scales of the feet larger, the 

 transverse scutellai of the toes extending nearl}' to their base. 

 Gampsonyx. 



B. Tomia distinctly indented. Tarsus considerably longer than the 



middle toe. First quill longest; none sinuated. % Tail nearly 

 equal to the wing, excessively forked, the outer feather about 

 twice as long as the inner, and much attenuated. Scales of the 

 feet rough, hexagonal; transverse scutellse only on the terminal 

 jDhalanx of the toes ; Nauclerus.^ 



* Pandion is the ouly orenus which shares this feature, but iu it the claws are con- 

 tracted iu thickness toward the under side, which is not the case iu the Elani, while 

 all the claws are of equal length. 



t Excepting certain Femes, as Elanoides and Baza, no other Butfonincc have less than 

 three primaries with their inner webs sinuated. The -Pernes differ from the Elani, 

 however, very essentially, in their bony structure, lacking the superciliary shield or 

 accessory piece to the lachrymal, which is simple and almost rudimentary, as iu Pandion. 



X The only instance, to our knowledge, in the entire family. 



§ The synonymy and chaiacters of this remarkable genus are as follows : — 

 NaucUrus Vigors, Zool. Journ. ii, 1825, 386. Type, Elanoides riocouri Vieill. 

 Chelictinia Lesson, 1843 (teste Gray, ubi '?). Same type. 

 Chelidopteryx Kaup, Mus. Senck. iii, 1845, 258. Same type. 

 C ypselojyteri/x Kauf, Weigm. Archiv, xvi, 1850, 31. 



Ch. — Bill much as in Ictinia, but less robust ; nostril unusually lar^e, oval, obliijuely 



