Maynard on Oolaptes auratus. 35 



liable to cause the outcropping of some ancestral character, 

 which has long been lying dormant, we have at once a 

 flood of light let in upon some of our most difficult or- 

 nithological problems. It will also tend to show from 

 what direction any given species had its origin. For exam- 

 ple, occasionally we have specimens of Pipilo erythrop- 

 thahniis here in the east with spotted scapularies. I have 

 one now in my collection in which the white marking on 

 the scapularies is very prominent and which was taken 

 in Burlington, Yt., and, upon an examination of a number 

 of Towhees taken in exactly the same locality, I find that 

 they are all unusually dark; in fact a dark local race had 

 been formed, for as is well known, some birds return yearly 

 to breed in the same locality and thus races are formed 

 which become more or less isolated. A pale normal bird 

 had quite likely invaded this territory occupied by the dark 

 race, a disturbance was the result of the union with one 

 of the males of the community, and the offspring was a 

 bird with spotted scapularies, showing, according to our 

 hypothesis, that his ancestors had spotted scapularies like 

 many of the western races, which in turn evidently had 

 their origin from the typical Mexican Tnaculatus. 



Again we frequently find ^'Juncos" in Massachusetts 

 during the migrations, having a well defined white band 

 on the wing, a character which might puzzle us to account 

 for even by this hypothesis. Thousands of miles intervene 

 between the present stock or perhaps a phase through 

 which the parent stock has passed, and the Junco Jiyemalis 

 of the east; yet the dominant ancestral peculiarity is there 

 and owing to the disturbance, the Gray Snow Bird, child 

 of parents with unmarked wings, exhibits the white wing- 

 bar of his remote ancestors. 



It is also a well known fact that the young of animals 

 often prove ancestral characters which are lost at a more 



