374 



Bulletin 258. 



Time and sequence of the mature molt. 



The first mature molt comes at the end of the first year of laying. 

 It seems to be a necessary renewal of the worn-out plumage. Feathers, 

 like clothes, wear out (Fig. 11). 



In the mature molt, it was found that the rotation followed closely 

 that of the pre-nuptial* molt before egg production commenced, — the 

 oldest feathers being shed first. The mature molt seldom began while 

 the hen was laying. Quite a few feathers might be shed earlier in the 

 season, and during 

 production ; but, in 

 most cases, the 

 shedding of feath- 

 ers ceased for a 

 week or two, — 

 often for a much 

 longer period, then 

 the entire plumage 

 was renewed. For 

 convenience, this 

 latter part of the 

 molt is termed the 

 " general molt." 

 During this molt, 

 some hens shed 

 only a few feathers 

 at a time in the 

 different feather 

 tracts, looking well clothed throughout the molt, while others shed almost 

 the entire plumage at once. This quick shedding gave a good oppor- 

 tunity to observe the feather tracts on a hen (Cover cut and Fig. 12). 

 The flight coverts, (the small, stiff feathers on the finger of the wing), 

 often persisted long after the other plumage was molted. These feathers, 

 which had been colored, were observed on several hens as late as April 

 following the molt, and were then apparently as firmly fixed as ever. 



PART II. AN ATTEMPT TO FORCE THE MOLT. 



On August 11, 1906, we arranged 232 Single Comb White Leghorn 

 fowls in six pens for the molting experiment. The details of housing, 

 feeding and management may be stated, in order that the reader may 

 have a complete mental picture Dt the experiments. 



Fig. 10. — Completely plumed with chick feathers a/ 54 



days. 



* Dwight — "Sequence in Plumage of Passerine Birds." 



