R. M. STRONG. 



there is an area of almost complete absence of normally formed 

 barbules (Fig. 2). The barbules of both the distal and the proxi- 

 mal rows in this region were represented only by stubs of the 

 proximal portions, and the stubs in the distal row were much 

 shorter than those of the proximal row (Fig. 3). To the unaided 



FJG. 2. Dorsal view of the abnormal region in one of the rectrices, the fourth from 

 the left side of the tail. < 6. 



eye the vane appears loose in texture at this point and, as in the 

 remiges, it is slightly narrower here. 



It has been impossible to determine the histogenesis of these 

 barbule stubs, but it seems to the writer unlikely that they represent 

 the entire structure produced in the feather germ. The occur- 

 rence of barbules of normal appearance among the stubs with no 

 intermediate conditions and the irregular fractured appearance of 

 the distal ends of the stubs point strongly towards the conclusion 

 that a distal portion has been broken away. There are a num- 

 ber of species of birds which normally have feathers with the 

 barbules broken off at certain fairly definite points near their 

 proximal ends in the distal portions of the more distal barbs as 

 has been observed by Meves ('55), Chapman ('96), Dwight (: oo), 



