280 University of California Publications in Zoology [Vol. 10 



similar in lower Palm Canon to what they are at Mecca; at least 

 is this true of those conditions immediately surrounding the song 

 sparrow. In Palm Canon, just the same as at .Mecca, the plants 

 foraged through are arrow-weed, mesquite, and small areas of 

 wire grass. 



It is probable that song sparrows in Palm Canon have been 

 there for at least several generations, for the senior author col- 

 lected a specimen typical of coopt ri there December 28, 1903. 

 It would therefore appear that the supposedly "susceptible" 

 song sparrow (at any rate in this race) is in reality not sub- 

 ject to quick modification of characters in the lifetime of the 

 individual, or through several successive generations. 



It is patent from geographic contiguity, as well as characters, 

 that Ihe colonies inhabiting Palm Canon and others of the canons 

 of the desert drainage of the San Jacintos, were originally 

 stocked from the Pacific side. The elapsed time has not been 

 sufficient for the impress by the new and strange environment 

 of modifications to a perceptible degree. 



It would appear that here, under perfectly natural condi- 

 tions, we have an experiment of just the sort demanded by 

 experimentalists to prove whether or not subspecific differences 

 .ire subject to abrupt modification by changed environment. In 

 this ease the characters are much more stable than has been 

 supposed (see Beebe, 1907). 



Melospiza lincolni lincolni (Audubon) 

 Lincoln Sparrow 



Found only in the Boreal meadows of Tahquitz Valley and 

 Round Valley. Here during duly we found them in fair abund- 

 ance in the wet. veratrum-covered cienagas, though the birds were 

 inconspicuous, and not readily seen. A large proportion of the 

 specimens secured were caught in mouse traps set for meadow 

 mice and shrews. Early in duly, at the time of our arrival at 

 the points where the species was encountered, the young were 

 already out ;\)\d flying about. 



Twenty-two specimens were preserved, twelve adults and ten 

 juvenals. nine from Round Valley (nos. 2097-2102, 2197-2199). 

 and thirteen from Tahquitz Valley (nos. 2916-2928). 



