INHERlTANCi; 03? FECUNDITY IN DOMESTIC FOWE- SIT 



from the different matings. The writer would, of course, be 

 glad if records were at hand for a large number of progeny for 

 ever}'- mating made. There are, however, practical difficulties 

 in the matter. The Maine Agricultural Experiment Station 

 poultry plant has accommodations for only about 600 adult 

 pullets per annum in spite of the fact that it is one of the largest 

 purely experimental poultry plants in the country." Now taking 

 all the experiments tQgether there are made about 300 separate 

 matings each year. It is simple arithmetic to show that under 

 the circumstances, if all matings were ec[ually represented, only 

 two pullets from each mating could be tested as to fecundity. 

 As a matter of fact all matings are not equally represented. 

 Some yield either no chickens, or too few to insure the develop- 

 ment of adult daughters. The aim has always been in this work 

 to put into the laying house for trap-nest records of fecundity 

 as many daughters from each one of as many matings as possi- 

 ble. Of course, only healthy, normal well developed pullets- 

 can be used in the work, since any other sort could not be de- 

 pended upon to give reliable normal results as to fecundity. 

 This means that, under the prevailing climatic conditions here^ 

 only pullets hatched between a rather narrow range of dates 

 (April I to June i) can be used in the fecundity. Those 

 hatched at other seasons will not give normal results. 



Altogether it will be seen that the character fecundity in fowls 

 is not one which lends itself readily to treatment in large masses- 

 of figures, desirable as such might theoretically be. The case is 

 very different from the study of the inheritance of plumage 

 colors in poultry, for example, where both sexes are available 

 for record and the records may be made while the chicks are 

 relatively young (or in some cases even unhatched) and before 

 they have time to die. If all students of the inheritance of pig- 

 mentation in poultry had been obliged to keep, house, and feed 

 every bird which was to furnish any record whatever, until 

 approximately one. and a half years after hatching, and could 

 have got records even then only from one sex (both of which 

 conditions obtain in the study of fecundity), it is plain that their 



" There are hatched annually on this plant from 3500 to 4000 chicks, 

 and facilities for handling adult stock make it possible to accommodate 

 over winter about 1000 birds of all sorts, including adult pullets, hens 

 and male birds. 



