OSTRICHES. 87 



FAMILY OF BREVIPPENNES. 



7. The Brevipennes (Plate 5, fig. 5.) are very large birds 

 that are entirely incapable of flying, and have rudimentary wings 

 only ; but they are remarkable for the strength of their posterior 

 extremities, which renders them excellent runners. Here, the 

 muscles of the chest not being required, as is the case in other 

 birds to make the strong efforts necessary to depress the wings 

 during flight, are very small, and there is no projecting keel in 

 the middle of the sternum for their attachment, as in other birds ; 

 this bone is in the form dfr a simple shield. It is to be observed 

 also, that all the Brevipennes want the thumb, and that, both 'in 

 the form of their beak and in their regimen, they are very analo- 

 gous to the Gallinaceae. This family is composed of two genera: 

 the Ostriches and the Cassowaries. The first have broad, flexi- 

 ble feathers, and the second are covered with narrow, stiff plumes, 

 almost like bristles. 



8. OSTRICHES, Struthio, (Plate 5. Jig. 5.) are very large 

 birds with long legs and tarsi, a long slender neck, and a very 

 small head ; they have only rudimentary wings, composed of 

 loose, flexible feathers with isolated barbs, which are entirely 

 unsuitable for flight, but which these animals make use of in 

 running. The beak, which is of moderate length, is soft at the 

 end ; the eye is large and the lids are fringed with eye-lashes ; 

 the tongue is short and rounded like a crescent ; the crop is 

 enormous, the gizzard very slrong, and the intestines volumi- 

 nous ; and above the cloaca their is a sort of large reservoir in 

 which the urine accumulates as in a bladder ; and this is the 

 only bird that urinates. 



9. Two species of Ostriches are known: one, proper to the 

 easjern continent, and characterised by having only two toes ; 

 the other, proper to America, which is recognisable by having 

 three toes. 



10. The Ostrich of the Eastern Continent, Struthio camelus, 

 (Plate 5, jig. 5.) is the largest of birds ; it attains six or seven 

 feet in height and weighs as much as eighty pounds; the head 

 and neck are thinly covered with feathers ; the back, breast and 

 belly are covered with black mingled with white and gray 

 leathers, and those of the wings and tail are white ; the thighs 

 are almost as naked as the neck, and of the two toes which termi- 



7. What are the characters of the Brevipennes? 



8. What are the characters of Ostriches ? 



9. How many species of Ostriches are known ? How are they Hi tin- 

 guished ? 



10. What are the characters of the Ostrich of the eastern continent ? 



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