( 563 ) 



SPOTTED OR CANADA GROUS. 



Tetrao canadensis, Linn. 



PLATE CLXXVI. Vol. II. p. 437 



According to Dr Richakdson, all the thick and swampy black- 

 spruce forests between Canada and the Arctic Sea abound with this 

 bird, and considerable numbers exist in the severest seasons as high as 

 the 67th parallel. I am informed by Dr Townsend that it is also 

 plentiful on the Rocky Mountains and the plains of the Columbia, from 

 which parts I have obtained specimens diflFering in nothing from others 

 procured in Maine and Labrador. I have also compared those in the 

 Edinburgh Museum, which Mr Douglass was pleased to name Tetrao 

 Franklinii, with several of my own, and feel perfectly confident that 

 they are all of one and the same species. 



In a male preserved in spirits, the mouth is of the moderate width 

 of 10^ twelfths ; the palate flat, with two longitudinal ridges, the pos- 

 terior aperture of the nares 8 twelfths long, strongly papillate on the 

 edges ; the tongue short, being only 7^ twelfths in length, triangular, 

 a little concave above, emarginate at the base, with long pointed pa- 

 pillae, disposed in two series, the tip somewhat obtuse. The oesopha- 

 gus is 65 inches in length ; its width from 10 twelfths to 8 twelfths for 

 the length of 3^ inches, where it opens into a globular sac 2 inches 9 

 twelfths in diameter, the space between the upper and lower aperture 

 of which is only 9 twelfths. The stomach is a very large and power- 

 ful gizzard, of an irregular elliptical fonn, 1^ inch in length, 2\ inches 

 in breadth ; the right muscle 9 twelfths, the left 11 twelfths in thick- 

 ness ; the tendons large and radiated ; the epitheUum tough, horny, 

 with two nearly flat smooth grinding surfaces. The intestine is 3 

 feet 2 inches long, with a nearly uniform width of 3 twelfths. The 

 coeca commence at the distance of 4 inches from the extremity, and 

 are 16^ inches long, their width 3| twelfths, excepting for 3 inches at 

 the commencement, where it is only 2i twelfths ; on their inner sur- 



