No. 633] INHERITANCE IN THE OSTRICH 307 



ciated with stimuli from secretions or enzymes of the 

 sexual organs. Yet occasionaly very young chicks, per- 

 haps only a week or two old, are to be seen performing 

 the same, though in an imperfect manner. They can 

 "roll" almost perfectly; a chick can inflate its neck, but 

 has insufficient strength to expel the air with enough 

 force to produce a "bromm"; and often one chick will 

 attempt to mount another which is resting on the ground, 

 and begin to sway from side to side in a ridiculous fash- 

 ion. May not these precocious activities be interpreted 

 as an acceleration of responses normally due to stimuli 

 of a sexual nature? Now they are performed wholly 

 apart from the usual stimuli and are of no adaptive nor 

 selection value at this early stage. They have become, 

 as it were, so integral a part of the organism that they 

 break out without the original stimulus; they have be- 

 come transmissible. They are hardly sufficiently general 

 to be comprised under the term "play" and, in the sense 

 of Carl Groos, to be regarded as preparatory to the real 

 business of life. Probably many activities of a similar 

 precocious nature could be brought forward where an 

 intensive study of an animal has been made. They serve 

 to show that a physiological action is not necessarily a 

 response to the stimuli which originally called it forth; 

 but may appear antecedent to and independently of them. 



Just as physiological activities may make a precocious 

 or accelerated appearance so it may be that acquired, 

 morphological characters at times appear in advance and 

 apart from the stimuli which originally called them 

 forth; they may become transmissible, though not ger- 

 minal in the factorial sense. It is submitted that the for- 

 mation of callosities, ordinarily developed as responses 

 to pressure and friction in the life-time of the individual 

 bird, has become thus accelerated, so that they arise at a 

 much earlier period, even within the egg, and apart from 

 the usual stimuli. Arising in this way a character is not 

 germinal in the sense of having factorial representation, 

 but is nevertheless transmissible. Though appearing 

 before hatching it is no more germinal than it would be if 

 developed as a definite response to the post-natal stimuli 



