74 Lincoln, Birds of the Clear Creek District, Colo. [j"^ 



favored. A minute snail which is found on this plant, proved to be the 

 attraction. They were noted weekly to April 3. 



A more recent visitation of this species occurred early in 1917, the birds 

 appearing in even greater numbers in the Creek valley and surrounding 

 country. A detailed account of this invasion was given by the writer in 

 ' The Auk,' Vol. XXXIV, 1917, p. 341. 



Lanius borealis. Northern Shrike. — Winter resident; common. 

 My own observations do not serve to verify the defense made of this bird 

 by others, who credit it with the destruction of English Sparrows. This 

 may be true to some extent where the bird frequents city parks, but I have 

 yet to see this species fall as its prey, while I have seen it capture 

 Tree Sparrows, Juncos, Chickadees, Horned Larks, and on one occasion 

 a Hairy Woodpecker was seriously crippled, but saved by my intervention. 

 A quart of wheat with half an ounce of strychnine, used judiciously, will 

 do far more toward eliminating the Sparrows in any one neighborhood, and 

 with less danger to the native birds. 



Lanius 1. excubitorides. White-rumped Shrike. — Only noted in 

 the spring migration although it should nest in this vicinity. The account 

 of habits under borealis does not apply to this bird if my observations are 

 correct, as I have never seen excubitorides kill a bird and believe their food 

 is principally of an insect nature. 



Vireosylva olivacea. Red-eyed Vireo. — Rare. A male and female 

 were secured August 18, 1911. They were feeding a young bird which 

 escaped. Other specimens taken May 26, 1912, and August 8, 1912. 

 Most of the Colorado records of this bird are of migrants and I believe the 

 above note is the first actual occurrence of their breeding, reported. 



Vireosylva g. swainsoni. Western Warbling Vireo. — Summer 

 resident; not uncommon. More frequently heard than seen. Occa- 

 sionally found in small groups (family parties, in all probability) in late July 

 or August. 



Lanivireo s. plumbeus. Plumbeous Vireo. — Rare. Only record, 

 a specimen secured June 2, 1912 (Coll. F. C. L. No. 386). 



Vermivora virginiae. Virginia's Warbler. — Migrant; not common. 

 First of spring usually noted about May 25, when the plum thickets are in 

 bloom. Not often seen in the fall. 



Vermivora c. celata. Orange-crowned Warbler. — Migratory; 

 common during both spring and fall migrations; the majority of those 

 taken being referable to this form, although a few of the next have also 

 been taken. 



Vermivora c. lutescens. Lutescent Warbler. — Migratory; rare. 

 Only two or three specimens of this variety have actually been identified. 



Dendroica a. aestiva. Yellow Warbler. — Summer resident; com- 

 mon. Arrives about May 15. 



Dendroica coronata. Myrtle Warbler. — Migrant; not common. 

 Generally associated with flocks of D. a. auduboni with which it may be 

 classed as the earliest of the Mniotiltidae to arrive. Rarely seen in the fall. 



