136 STEGANOPODES. 
Cathartes burrovianus of Cassin (Pr. Acad. Philad. ii. p. 212) has been considered 
by most writers to be a small example of the common Turkey Vulture of North 
America; but Mr. Ridgway has recently examined the type-specimen, and states that 
it is identical with C. urubitinga of Pelzeln, the very distinct and well-known Orange- 
headed Turkey Vulture of South America. 
This species was described by Cassin in 1845 from a single specimen presented by 
Dr. Burrough to the Academy of Natural Sciences of Philadelphia, and was said to 
have been obtained in Vera Cruz, Mexico. Considering the number of naturalists 
who have collected in all parts of Central America during the last fifty years, it is not 
a little surprising that no one has ever noticed so conspicuous a bird as an Orange- 
headed Turkey Vulture. 
In addition to the head being differently coloured from that of C. aura, the species 
is distinguished by the feathering on the hind-neck, which is continued to the nape. 
In a letter to Mr. Ridgway Prof. A. Dugés describes a downy young bird from 
Guanajuato, which the latter thinks may be the young of C. burrovianus. At present 
we cannot believe that the Orange-headed Vulture is an inhabitant of any portion of 
Central America. 
In Amazonia, especially near Para, C. urubitinga is said by Dr. Goeldi to be not 
uncommon, being usually found in the vicinity of water. The food consists chiefly of 
dead fish, but living ones are occasionally captured. 
The Californian Vulture (Pseudogryphus californicus) was supposed by Don Alfonso 
Herrera to be found in the Valley of Mexico [La Nat. (2) i. pp. 175, 319], but, from a 
MS. note which he has kindly sent us, it appears that there are no trustworthy data of 
the occurrence of this species in Mexico. 
Order STEGANOPODES. 
The chief feature distinguishing this Order is the interdigital web, which unites 
even the hallux or hind toe to the others, hence the name of “ Totipalmati” given to it 
by old writers. Other notable characters are the desmognathous palate, the absence 
of basipterygoid processes, and the marked features of the pterylography, &c. 
Mr. Pycraft has recently written an important paper on the osteology of the 
Steganopodes (P.Z.S. 1898, p. 82), and we have here adopted his conclusions, with 
only a slight deviation from the arrangement of the various groups. 
In the Steganopodes the following Families occur, all of which have representatives 
in the Central-American Avifauna:—1. Phaethontide, 2. Fregatide, 3. Pelecanide, 
4, Sulide, 5. Phalacrocoracide, 6. Plotide. 
