620 HOODED MERGANSER. 



ing two flat grinding surfaces. The proventricular glands are very 

 small, forming a belt 1^ inch in breadth. The intestine is 51 inches 

 long ; its width from 3^ twelfths to 2| twelfths ; the coeca 9 twelfths 

 long, 2 twelfths wide, 3 inches ft-om the extremity ; the rectum 5 twelfths 

 wide, forming at the end a globular cloaca, 1 inch in width. Lobes of 

 the liver nearly equal, 2 j inches in length ; gall-bladder i inch long. 



Trachea 6J inches long, much flattened, for 3 inches diminishing 

 from 3^ twelfths to 2^ twelfths, then enlarging to 4^ twelfths ; from 

 this place to the tympanum it is of a trigonal form, with an acute car- 

 nia anteriorly, and the rings are widely separated. There are 102 rings, 

 besides 8 which are united and form part of the tympanum, which is 

 of an irregular form, projecting anteriorly with a rounded bulge, and 

 dilated on the left side, its greatest breadth 9 twelfths. The bronchi 

 are of moderate length, the left with 32, the right with 26 half rings. 

 The muscles as in the other species ; the contractor muscles exceeding- 

 ly large at the upper part. 



RED-NECKED GREBE. 



POBICEPS RUBRICOLLIS, LatH. 

 PLATE CCXCVIII. Vol. III. p. 617. 



Female from Dr T. M. Brewek. Length to end of tail 19^ inches, 

 to end of wings 17^, to end of claws 24| ; wing from flexure 7| ; tail 

 If ; extent of wings 32J ; bill along the ridge If § ; tarsus 2j% ; hind toe 

 {^, its claw ^1 ; second toe l^, its claw || ; third toe 2i^, its claw ^^ ; 

 fourth toe 2^^, its claw ^^. 



The mouth is narrow, 9^ twelfths in width ; the palate slightly con- 

 vex, with two faint lateral ridges on each side ; its anterior part ex- 

 tremely narrow, with three longitudinal ridges, the lower mandible still 

 narrower, and deeply channelled. Tongue 1 inch 7 twelfths long, slen- 

 der, tapering to a thin horny point, trigonal, as deep as broad, fleshy 

 and concave above, horny beneath. (Esophagus, a be, 10 J inches long ; its 

 width uniformly | inch alongthe neck; the proventriculus, be, however, is 

 dilated to a very large ovate sac nearly 1 J inch broad, 1 inch 9 twelfths in 



