586 Mr. Yak 11 ELL o» the Trachece of Birdu. 



tent of surface for the insertion of large and powerful pectoral 

 muscles ; the enlargement at the bottom of the trachea in all of 

 them is of bone only. The Wild Duck may be considered the 

 type of this division. 



Die Eider Duck, King Duck, Velvet Duck, and Scoter, pos- 

 sessing some characters common to the preceding class, and 

 others belonging to that next in succession, appear to supply the 

 link between these two divisions. I regret that the extreme 

 rarity of three of the species last named has hitherto prevented 

 my obtaining any examination beyond that afforded by the exter- 

 nal part of preserved specimens in collections ; and I am there- 

 fore vniable to state their comparative structure. 



The next division of true Ducks includes in the followins; or- 

 der the Red-crested, the Pochard, Ferruginous, Scaup, Tufted, 

 Harlequin, Long-tailed, and Golden Eye ; and their general 

 distinctions, internal as well as external, compared with those 

 of the birds of the first division, will be found of an opposite 

 character. Externally they exhibit the neck and wings short, 

 the latter only reaching to the origin of the tail-feathers ; the 

 tarsi short and compressed ; the hind-toe lobated, and an ex- 

 tended web to the inner toe. '^I'hey frequent the sea, or the 

 deep parts of the largest fresh-water lakes, and have been 

 called oceanic Ducks ; seldom seen on land ; their walk em- 

 barrassed from the backward position of the legs, but dive 

 constantly and with great facility, taking their prey at various 

 depths below the surface ; their food finned and shell-fish, ma- 

 rine insects, but little or no vegetable production ; their powers 

 of flight moderate. Of their soft parts, the oesophagus is capable 

 of great dilatation ; the stomach is a muscular gizzard ; but 

 the internal cavity increases in size, those of the Long-tailed 

 Duck and Golden Eye most resembling the stomach of the 

 Mergansers ; the intestines and ca?cal appendages are shorter, 



the 



