144 



AVES. 



membrane ; sometimes there are two similar membranes, and at others they 

 are entirely wanting, and the toes are completely separated ; it sometimes 

 also happens, though rarely, that they are bordered all along, or palmated to 

 the very end; in fine, the thumb is deficient in several general circumstances, 

 all of which have an influence on their mode of life, which is more or less 

 aquatic. Almost all these birds, the ostriches and cassowaries excepted, have 

 long wings, and fly well ; during which action they extend their legs back- 

 wards, differing in this from all others, which fold them under the belly. 

 In this order we establish five principal families, and some insulated general 



FAMILY I. 



BREVIPENNES. 



THESE birds, although similar in general to the other Grallatoriae, differ 

 from them greatly in one point the shortness of the 

 wings, which renders flight impossible. The beak 

 and regimen give them numerous affinities with the 

 Gallinacese. 



It appears as if all the muscular power which is at 

 the command of nature, would be insufficient to move 

 such immense wings as would be required to support 

 their massive bodies in the air. The sternum is a 

 simple buckler, and is deficient in that ridge which is 

 found in all other birds. The pectoral muscles are 

 thin and delicate, but the posterior extremities regain 



what the wings have lost the muscles of the thighs, and of the legs in 



particular, being enormously thick and stout. 



The thumb is always deficient. The number of phalanges in the ostrich, 



commencing with the internal toe, is 4, 5, cassowary 3, 4, 5, which amount 



to the number common in birds. They form two genera. 



STRUTHIO, Linnaus. 



The Ostriches have wings furnished with loose and flexible feathers, but 

 still sufficiently long to increase their speed in running. Every one knows 

 the elegance of these slender-stemmed plumes, the barbs of which, although 

 furnished with little hooks, always remain separate, contrary to what takes 

 place in most other birds. Their beak is horizontally depressed, of a moderate 

 length, and blunt at the end; their tongue short, and rounded like a crescent; 

 their eye large, and the lid fringed with lashes; their legs and tarsi very long. 

 They have an enormous crop, a large sac between the crop and gizzard, 

 voluminous intestines, and a vast reservoir, in which the urine accumulates as 

 in a bladder, being the only birds which can be said to contain urine. But two 

 species are known, each of which might form a separate genus. 



Struthio came/us, Lin. (The Ostrich of the Eastern Continent.) But two 



