The Song Sparrows 



tinguished is the more 

 interesting because it 

 sets at defiance one of 

 the foremost canons of 

 Song Sparrowdom; viz., 

 that individuals shall in- 

 crease in size northerly. 

 Thus, the San Diego 

 Song Sparrow, M. m. 

 co op eri , has a wing 

 length of mm 63 ; rufina 

 of British Columbia, 

 mm 68 ; canrina from 

 Yakutat Bay, mm 72 ; 

 and the giant sanaka 

 from the Aleutians, mm 

 85. The Aleutian Song 

 Sparrow is, thus, more 

 than twice as big a bird 

 as ours in southern Cali- 

 fornia. Pusillulas wing 

 length, as given by Pro- 

 fessor Robert Ridgway, 

 the original describer, is 

 only mm 58.4. 



Life with piisillula has 

 been reduced to very 

 simple terms. 'There' 

 in a salt marsh, is just 

 the same as 'here,' so 

 where is the use of fash- 

 ing one's self about quick 

 transportation? No 

 need ; ergo, arrested wing 

 development; that is, 

 shorter wings. 

 That substantially uniform conditions have prevailed for ages in 

 the marshes of San Francisco Bay, there can be no doubt. Today an 

 intricate system of tidal arteries and capillaries supplies moisture to 

 acres of salicornia, a succulent round-stemmed plant growing in rank 

 profusion to a height of one or two feet; and each of these sodden acres 

 harbors a legion of molluscs, nemertines and crustaceans. There is 



Taken in Santa Barbara Photo by the Author 



SONG SPARROW ABOVE SALICORNIA 



NOT M, in. pusillula. but M. in. cooperi IN A brackish marsh, 

 "THE ESTERO" 



350 



