CHIONIDID^. 389 



FAMILY Y. 



Chionidid^.* The Sheath-hills. 



Gen. Chaeac. — Bill moderate, the eulmen much arched to the tip, the sides 

 much compressed ; the nostrils basal, lateral, and protected by a bony 

 covering, or only partly closed by a horny membrane; the wings long and 

 pointed ; the tail moderate ; the tarsi short and strong ; the toes long, and 

 the anterior ones united at their base, the hind toe short and elevated. 



This is a family containing a few species whose 

 characters are so curions as to liave rendered tlieir 

 position in tlie ornithological series somewhat doubt- 

 ful. They have a short and stout bill^ which is 

 compressed at the tip and considerably arched. 

 The nostrils are situated at the base of the upper 

 mandible, and protected by a more or less inflated 

 cartilaginous plate^ an appendage the use of which 

 is rather obscure. Like the birds of the preceding 

 family, they have long and pointed wings ; their 

 tarsi are of moderate length and thickness, naked 

 and reticulated quite up to the articulation, and 

 terminated by four toes, of which the anterior are 

 tolerably long, and the posterior small and slightly 

 elevated upon the back of the tarsus. These singular 

 birds are met with upon the sea-shores of Patagonia, 

 New Zealand, and Australia, and also upon many of 

 the islands of the Antarctic Sea. 



* Xfoj'ioc, ohionios, snowy. 



