Vol. xxxvin 



1920 



J Lincoln, Birds of the Clear Creek District, Colo. 63 



In almost every case the actual specimens have been secured and 

 preserved, my collections from the district numbering about five 

 hundred specimens, and in no case have species, based upon purely 

 visual observations, been included which would in any sense con- 

 stitute " records " for the State avifaunal list. Compilations have 

 in this instance also been generally avoided, for, while the pioneer 

 literature on the State's birds gives many interesting notes from 

 this region (visual or specimens unpreserved) the absence of sub- 

 sequent confirmation as well as their general indefinite nature, makes 

 their authenticity a matter of grave doubt. I have accordingly 

 confined myself to my own observations and collections with a few 

 notes on certain species from the collections of the Colorado Mu- 

 seum of Natural History and the private collection of Mr. Egmont 

 Rett, now of the same institution. 



Mr. Rett's work in the valley began at approximately the time 

 that my own ended, and has continued without interruption up to 

 the present time. In addition to securing specimens which serve 

 to confirm several of the writer's observations, he has obtained 

 others that add species to the list. So with a view toward com- 

 pleteness, I proposed that he permit me to incorporate his notes 

 and records in the present paper, to which he has graciously con- 

 sented. I accordingly desire to take this opportunity to express 

 to him my appreciation of bis hearty co-operation. 



.ffichmophorus occidentalis. Western Grebe. — Accidental. One 

 record; a specimen taken on Mud Lake, October 29, 1916, is preserved 

 in the Museum collections. 



Colymbus n. californicus. Eared Grebe. — Mr. Rett reports 

 Eared Grebes as fairly common of late years on Mud Lake during mi- 

 grations. A few killed there every year by hunters who know them 

 (together with the next) as " hell-divers." 



Podilymbus podiceps. Pied-billed Grebe. — Not common, but 

 still noted regularly throughout the summers on the lakes, where they no 

 doubt breed. 



Larus delawarensis. Ring-billed Gull. — - Rare. Four examples of 

 this bird observed on the lakes at Berkeley, September 22, 1912. 



Sterna forsteri. Forster's Tern. — Rare. Mr. Rett reports two 

 birds on the Berkeley lakes during September, 1916. These lakes offer 

 an abundant food supply and the species should be more common, at least 

 during migrations. 



