RlDGWAY on a New Species of Peuecea. 219 



be more than a seasonal variation. The Texas specimens, (now 

 in the collection of the National Museum,) collected, respectively, 

 April 10 and 29, and August 11, 1879, agree in every respect with 

 those from Illinois, in the points which distinguish the latter from 

 true aestivalis, and, being in very perfect plumage, leave no doubt, 

 in my mind as to their distinctness from that bird. Whether they 

 are a different species, or merely a western form of aestivalis, the 

 material at hand is not sufficient to determine ; but as, in our haste 

 to degrade to the latter rank a Western bird more or less closely 

 resembling P. aestivalis, two errors have already been made in 

 the cases of P. cassini (Woodh.) and P. arizonae, Ridgw., — and es- 

 pecially since a very wide area exists between the habitat of P. 

 cestivalis and P. illinoensis in which no Peucaea is known to exist, — it 

 may answer the present purpose quite as well to consider the latter 

 in the light of a distinct species, until its intergradation with P. 

 aestivalis be proven : at least a safe procedure in cases of the kind 

 under consideration. In view of the facts above brought forward, 

 I have concluded to characterize the Peuecea of the semi-prairie dis- 

 tricts extending from Southern Illinois to Central Texas as a new 

 species, and propose for it the specific name of illinoensis, this being 

 the only form of the genus which, so far as known, occurs in the 

 State of Illinois. Its characters are as follows : — 



Peucaea illinoensis* Ridgw. — The Oak-woods Sparrow. 

 Sp. ch. — Adult: Above sandy ferruginous, indistinctly streaked with 

 light ash-gray, these streaks broadest on the back and middle line of the 

 crown ; interscapulars sometimes marked with narrow central streaks of 

 black. Outer surface of the wings light ferruginous, the greater coverts less 

 reddish and edged with paler ; tertials dusky brown, bordered terminally 

 with pale reddish ashy ; outer surface of the secondaries ferruginous. Tail 

 uniform grayish-brown, the edges of the feathers more ashy. Sides of the 

 head and neck, throat, jugulum, and entire sides, deep dingy-buff, this 

 color most distinct across the breast, paler on the throat and chin ; a post- 

 ocular streak of ferruginous along the upper edge of the auriculars ; sides 

 of the neck streaked with ferruginous ; an indistinct dusky streak on each 



* PEUCiEA ILLINOENSIS. 

 " Peticcea cestivalis," Ridgway, Am. Nat., July, 1872, 430 (Wabash Co., 

 Illinois); Ann. X. Y. Lye, X, Jan. 1874, 373 (do.) ; Pr. Boston Soc, XVI, Feb. 

 18, 1874, 308, 326 (do.; summer resid.); Bull. Xutt. Orn. Club, III, Oct. 1878, 

 164 (" extremely local and quite rare"). — Nelson, Bull. Essex Inst., IX, 1877, 

 36, 49 (Mt. Cannel, Wabash Co., and Fox Prairie, Richland Co., Illinois). 

 Peuecea illinoensis, Ridgway, MS. 



