EDITORIAL. 1005 



be with horses and cows and the information sought is to be applied 

 to their breeding, much time may be saved b}' experimental work with. 

 mice, guinea pigs, rabbits, and other prolific mammals. 



The discovery of a dominant character in the color pattern of a 

 rabbit may require nuiny generations of rabbits but only a compar- 

 atively short space of time. Once discovered, the observations may 

 be transferred to the horse to determine if the same character is domi- 

 nant there, with a saving of much time. Such questions as the 

 regulation of sex, telegony, maternal impression, and inheritance of 

 acquii'cd characters are of great interest to biologists and j)i'actical 

 breeders alike. Small animals lend themselves to studies of this kind, 

 and may give both theoretical results and practical indications. Re- 

 cently much light has been thrown on the subject of the determination 

 of sex by studies with moths, grasshoj)pers, the cherry bug, and other 

 insects. 



Conditions at some of the stations have been too unsettled to war- 

 rant the inauguration of a work which may take many A^ears before 

 appreciable results can be secured. The more stable conditions which 

 now prevail, and the special research fund, offer many inducements 

 for men who have the proper training and are content to work indus- 

 trioush' and continuously along one line for a term of years. 



With our present knowledge there seem to be three main lines which 

 offer great oj^portunities : (a) Experimental breeding with discon- 

 tinuous variations; (b) statistical study of continuous variations; 

 and (c) microscoj)ic study of the minute constituents of germ cells. 

 P^ventually we shall have to seek explanations for the phenomena of 

 heredit}^ in phj'siological chemistry and molecular phj^sics, but for 

 the present there is abundant opportunity for studying experiment- 

 ally the problems which bear more directly upon the practical work 

 of the breeder. . 



