436 Mr. Yarrell on the horni/ appendage^ SfC. 



moisture J* and the partial separation of the membrane that had 

 lined the interior. 



I have observed after the first or second natural perforation, on 

 Iremoving a small part of the shell to obtain a partial sight of the 

 chick, that this hard point at the beak v^as pressed against the 

 shell or through the orifice by repeated efforts, and any change 

 , in the position of the egg produced after a short time a new frac- 

 ture in the shell, distinct from the former, depending on the 

 altered situation of the bird. 



On the twenty-first day this stage of the existence of the young 

 of the Common Fowl is completed, and from the particular posi- 

 tion in which it is placed within the shell, it will be evident, its 

 strongest efforts are exerted against each end of the egg : the legs 

 are stretched out downwards, and the head and neck raised, the 

 shell already partially divided, either by separate apertures or in 

 a continued line, opens as it were by a hinge, and the smaller 

 portion is frequently inserted or cupped within the larger. 



During the first twenty-four hours after exclusion from the 

 shell, the natural warmth of the hen is all that appears necessary 

 to the perfectly formed bird : the down spread over its body be- 

 comes dry, the beak hardens, and the small horny protuberance 

 on the point having performed the important office of dividing the 

 shell, is easily separated by the edge of the thumb nail of the 

 attendant, as the chicken passes by hand from the nest to the 

 coop, or remains to be removed by the chicken itself in its early 

 attempts to pick up food. If examined after the second or third 

 day, a light coloured mark only is perceivable on the spot formerly 

 occupied. 



In the young Pigeon this appendage to the beak is large and 

 strong, and as these birds are seldom handled during their first 

 fortnight, and are fed by the insertion of the beak of the parent 

 Pigeon, between the mandibles of the young bird, this horny 

 point remains fixed much longer than in the former instance. I 

 have seen it retained after ten or twelve days. 



* Eggs of the common fowl during incubation lose in weight on an average 

 about eight grains per day. 



