TRIPLET CALVES. 267 



tary control. An important question in all such cases concerns 

 the germinal genesis of the individuals included in the multi- 

 ple pregnancy. Did the individuals thus growing together in 

 the uterus arise from the separated blastomeres of a single 

 ovum, or from several distinct ova? In most cases the only 

 data which can be obtained on this matter arise from an exami- 

 nation of the external soinatic characters of the individuals con- 

 cerned to see whether or not they are identical. 



It should be understood that the preceding, somewhat de- 

 tailed, statement of the more important general biological prob- 

 lems to which cases of multiple gestation relate, is made for 

 purposes of general orientation in regard to specific data dis- 

 cussed in this paper. It is also hoped that it may sen^e to indi- 

 cate the kind of information that it is desirable to have recorded 

 by those who may chance to be able to observe cases of multiple 

 birth in the domestic animals. It is evident from the discussion 

 given above that cases of this sort have significance for the biol- 

 ogist and the stockbreeder quite beyond the merely casual curi- 

 osity which they excite as "freak"' occurrences. From the 

 standpoint of the practical breeder it is highly important that 

 the phenomenon of multiple gestation in normally uniparous 

 animals be carefully studied. Any definite and heritable in- 

 crease in the fecundity and fertility of the domestic animals, 

 if it can be gained without loss of other desirable qualities, is 

 greatly to be desired. Cases of multiple gestation are the '''fa- 

 vorable variations ' which must serve as the foundations for 

 the creation of more fertile breeds and races. What may be 

 accomplished in this direction has been splendidly demonstrated 

 by the work of Dr. Alexander Graham Bell with sheep (see 

 footnote p. 275). 



Finally it should be said that this general, introduction is dis- 

 tinctly not to be regarded as a statement of problems which 

 are to be definitely and completely solved by the data presented 

 in this paper. , 



