MERGANSER. 
Mergus Serrator, Ind. Orn. ii. p. 829. 4.—Sepp. Vog. iit. tab. 124. 125.—= 
Ger. Orne v. t. 509- 
Der Haubentaucher, Schr. d. Berl. Nat. Fr. iii. S. 374. t.7. f. 5. 
Red-breafted Merganfer, Gen. Syn. vi. p. 423.—Edw. t. 95.—Lin. Tranf. iv. 
p- izi. tab, xvi. f, 1.2. the windpipe of the male. 
NX7E do not find that externally the male and female of this {pecies 
have been at all miftaken by authors, but ftill the intuitive 
naturalift will obferve the fame internal difference to exift as takes 
place in the greater fpecies. The male has an enlargement of the 
trachea about the middle of its length, confifting of bony plaits of the 
fame texture as the reft of it, the lower part of it ending in a large 
and remarkable bony cavity, of an irregular heart fhape, with two 
openings on one fide, and one on the other: all of which are covered 
with fine membranes *, and from the bottom of this the two bronchiz 
fpring, which there dividing, lofe themfelves in the lungs. 
Mergus imperialis, Ind. Ora. ii. p. 829. 3.—Cett. uc. Sard. p. 326. 
HIS is the fize of a Goofe: the body is variegated with black,. 
brown, and grey: the head is without a creft: the prime quills 
are black, and without any fpeculum: bill and legs rufous white: 
tongue ciliated. 
Inhabits Sardinia. 
* See the plate in Liz, Tran/. above referred to. 
Supp. If. | Xx 
337 
2. 
RED- 
BREASTED 
M. 
DescriPrion, 
$. 
IMPERIAL 
M 
DESCRIPTIONs 
PLace, 
