408 Dr, A, Hall on the Mammals and Birds 



Bill reddish yellow or crimson Bill orange, with a faint streak of 

 tipped with black. black on both mandibles near 



the tip, which is pale. 

 Tarsus red, 1 inch long. Tarsus and web black, the for- 



mer 1§ inch long. 

 Length 15 inches ; alar expanse Length 20 inches ; alar expanse 

 30 inches. 46 inches. 



From this comparative view of these two birds, there can be 

 little doubt but that they are distinct. Under present circum- 

 stances, however, I do not wish to establish a new species, for 

 they are sufficiently numerous ; I much rather prefer ranking it 

 under the head of S. Hirundo with a point of interrogation after 

 it, thus implying my doubt as to its being' in reality the bird men- 

 tioned by authors under that name. The specimen from which 

 my description is taken is in the Museum of the Natural History 

 Society of Montreal. This bird differs also very materially from 

 the Sterna Boysii, 



S. arctica. Arctic Tern. 

 S. argentea of Brehm ! 

 S' macroura of Newman. 

 Sterna macroura. . Baird ! 



v.s.p. Bill orange tipped with black ; legs and feet scarlet ; 

 irides brown ; eggs 2 to 3, light yellowish brown or bluish grey 

 potted irregularly with brown. 



Dorsal aspect. Crown and nuchal- region jet black ; mantle 

 pearl grey; rump and tail coveits white; outer vane of the 1st 

 primary black ; outer vanes of all the others, as well as the tips, 

 and a stripe down the inner vanes along the shafts, hoary grey, 

 verging to black at the tips ; outer vane of the lateral tail feathers 

 black ; of all the others pearl grey ; inner vanes of primaries, se- 

 condaries, and tail feathers white. 



Ventral aspect. Cheeks, throat, vent, tail coverts, and wings 

 linings pure white ; all other parts pearl colour. 



1st primary longest ; wings extending long over the tail ; length 

 14 inches ; alar expanse 30 inches ; length of the bill from the 

 rictus 1 inch 9 lines ; tarsus and toes small ; middle toe, without 

 the nail, equal to the tarsus. Li two other specimens before me, 

 the new lateral tail feathers only have their external vanes pearl 

 grev, and not black at all, and all the other tail feathers white. 

 This Tern is the most common one in this district. 



