Early Development of the Hen's Egg. 103 



surface views, a weak solution of Flemming's chromo-osmic acid is 

 excellent and has but one disadvantage, viz., that after its use the 

 egg usually can not be sectioned. 



III. Some IN'otes o:^ the Laying Habits of the Hen. 



The behavior of the hen during the breeding season would make an 

 interesting topic for the student of animal behavior; for while one 

 sees many evidences suggesting that domestication has wonderfully 

 influenced the behavior of the hen, yet there are continually cropping 

 out certain habits that evidently have been derived from her wild 

 ancestors, and which even centuries of domestication have not com- 

 pletely eradicated. One of the most noticeable of these is seen in 

 connection with the nest building. The hen never carries building 

 material to the nest, but she often stands in the vicinity of the pro- 

 posed site and makes a futile effort to get straws and feathers into 

 the nest by tossing them over her back. In several of the other 

 Gallinse this same habit is observed. Many species of this group of 

 birds are accustomed to building their nests in tufts of grass, where 

 an abundance of material is ready at hand, and its building is a 

 comparatively simple matter, consisting in the arrangement of the 

 grass. Occasionally, however, other birds (e. g., the quail) will en- 

 gage in exactly the same futile effort as that cited above for the 

 hen, only in a more pronounced manner. 



The writer's study of the habits of the hen was not carried on 

 with any intention of winting a paper on its behavior, but rather 

 in order to find out if there is any regularity in its laying habits. 

 If one is to collect eggs for the purpose of obtaining a close series 

 of stages, it is of the greatest importance to be able to tell just 

 when to kill the hen in order to secure a desired stage. It is only 

 in this way that one can hope to obtain sufficient data for a cor- 

 rect interpretation of the history of development. 



It is commonly supposed that the hen lays very irregularly, and 

 while the writer finds this to be true for some few hens, yet in 

 most cases he was soon able to predict the time of laying to within 

 a few minutes. This is especially true of that class of hens laying 

 daily. Such hens are found to lay slightly later each day, and 



