Abstracts. 221 



transmits the tendency for high or low butter- fat percentage to 

 the offspring; and the third that both parents contribute to the 

 butter-fat percentage transmission. The results of these experi- 

 ments show that the third of these claims is correct. Such being 

 the case the dairyman who wishes his breeding operations to 

 progress successfully will find it desirable to examine both sides 

 of his animals' pedigrees carefully. Thus, today, the Jersey 

 breeder pays a good deal more attention to the sires' side of the 

 pedigree than he does the dams' side of the pedigree when in 

 truth both sides are equally important. 



MODE OF TRANSMISSION OF MILK QUANTITY AS 



SHOWN BY FIRST GENERATION CROSSES OF 



DAIRY AND BEEF BREEDS OF CATTLE.* 



This paper is a further discussion of the results indicated 

 in the abstracts on Inheritance of Milk Yield. 



THE LIFE CYCLE OF APHIDS AND COCCIDS.* 



To attempt to epitomize the life cycle of the aphid is like 

 trying to draw an orderly sketch of Chaos. But after all, the 

 confusion may be more seeming than real and certain rules, be- 

 set though they may be with exceptions, govern the life of even 

 the aphid. 



The gamogenetic egg is an outstanding argument for the 

 conclusion that the aphid of the North is holding more closely 

 to its prehistoric past than are those that spend their lives where 

 the successive seasons of the year offer a constant source of 

 food. For in the region of real winters there is no member of 

 the family Aphididae (in its restricted sense) whose total life 

 history has been worked out, that is known to pass its annual 

 cycle without exhibiting a concluding generation comprising 

 both sexes. The aphid, then, starts its life cycle like a typical 

 insect — in the fertilized egg. 



*This is an abstract from a paper by John W. Gowen having the same 

 title and published in Proceedings Soc. Promotion Agricultural Research. 



*This is an abstract from a paper, having the same title, written by 

 Edith M. Patch and published in Annals of the Entomological Society 

 of America, Volume XIII, No. 2, pp. 156-167. 



