428 XORTir AMEIUC.VN HIRDS. 



llAmrs. Tn iv<rar.l 1.. distinctive i.oculiaritie.s in l,i,l.it.s and manners 

 of this i(n-in (.niroase, if it ])ossosses any, (nir inlbrniation is qnite limited' 

 In Its external inarkin-s and in si/e it ai)i.ears to be readily distin.niisjuil.le 

 from the T. (Hmnrm either speeitically m as a well-marked interior race 

 Mr. J. Iv. Lord refers to it in his acconnt of the oh>^vHvm, where he states 

 tlint hetween the Cascades an.l the Ifocky INfonntains the Dusky Grouse 

 ai.].ears t., 1.,! rei.laced by a well-marked variety, if not a distinct species In 

 size It IS a trille smaller, but the -reat mark of distincli.m is the entire 

 absence of the white band at the end of the tail. In their habits, in their 

 l-onods (,i arrival and departure, or rather of a].].earance and disai.pearance 

 the two varieties are pronounced to be, in every re.s].ect, similar. Jn re.>ard 

 to their unexplained di-sappearance and reappearance, iAIr. Lord is of^the 

 opinion that these birds do n.^t migrate, l.ut only retire into the thickest 

 trees, and, living on the buds, pass the winter thus sheltered in the tree- 

 tops. 



Captain IJlakiston thinks that this si.ecies is the form that inhabits the 

 interior of I5ritisli North America, and refers the figure of the male in 

 Kichardson's Fmum to the rh'har,hmi,~i\^^ I5Iack-tailed and smaller species 

 In his wanderings he met with these birds only in or near the pine woods 

 on the slopes of the Kocky Mountains; but, having killed only females he 

 could not feel certain of the species. These (irousc range towards the 

 laeihc as far as the Cascade Mountains of Oregon and British Columbia 

 and along the Jiocky Mountains from the head-waters of the I'latte to the 

 Liard Eiver, a tributary of the Mackenzie. When the ranges of the two 

 species are fully defined, he thinks the T. rkhanhonl will be found the 

 more northern bird. 



The eggs of Tdmo rivhmUoni are very similar, except in size, to those of 

 the ofer^^nw, resembling them closely in their ground-color, as well as in their 

 markings. In ^ the specin;eiis in ti.e cabin(;t of ihe Boston Nafural'Hislory 

 Society the .s])ots are smaller, a little less distinct, and less numerous. 

 The eggs are 1.75 inches in length, and from L3o to L3G inches in breadth. 



Genus CENTROCERCUS, Swaixson. 



Ccnlroccrcus. Swain-.son-, F. H, A. II. 1831, 49(;. (Typ,., Tetrao uvoplumanus, Bon.) 



Gns-. C„AR. Tail o.xr,..sively lo,ifr,l,o,R.,I (lon.iror than tl„> winj?,-), ouneate, tho feathers ' 

 a 1 hmceolnto and attoauato. Lowe,- tliroat an.l ..i.kvs of the nook with ..tinene.l, apparently 

 a .raded, spnunts foather.s. Xasal fossa, e.xtending very far forward, or along about two 

 tlnnls of tho cuhnen. Color niottlo.l ydlowish-j^^rayish and dti.skv above; beneath 

 wh>t,..h with blaek abdominal patch. Stomach not muscular, but soft; as in the Raptorial 



