Abstracts. 233 



0.723 per cent higher in butter-fat than the morning milk 

 throughout the whole lactation. No appreciable difference oc- 

 curs in the solids-not-fat. 



For the clear understanding of the bearing of these data 

 on the hypothesis to account for the mechanical mechanism by 

 which the solids are released into the milk, it seems best to re- 

 state them in as simple terms as possible. These hypothesis may 

 be placed in three groups : 



A. The mammary gland cells break loose bodily and dis- 

 integrate in the alveoli. 



B. The portion of the cells toward the alveoli become 

 loaded with solids, break loose from the basal portion and dis- 

 integrate to form the milk solids. 



C. The cells of the mammary gland secrete the materials 

 of milk solids without themselves breaking down. 



These data offer criteria between the theories to account 

 for the secretion of the milk solids. On the cell disintegration 

 theories the cell must contain a fixed quantity of solids-not-fat 

 while the butter-fat varies so that in the longer interval between 

 milkings the cell accumulates less fat than in the shorter time, 

 or taken the other way, the cell contains relatively more protein 

 and sugar than fat as the interval between milkings lengthens. 

 This is contrary -to our knowledge of fat formation for it is 

 commonly accepted that first comes the cells composed largely 

 of protoplasm and that as time goes on this cell is more and 

 more loaded with fat at the expense of the protoplasm. Unless 

 these mammary cells behave very differently in the formation 

 of this fat than other body cells this variation is enough to seri- 

 ously discredit the hypothesis of cell disintegration to account 

 for these milk solids and in fact, to make it an absurdity. Fur- 

 thermore, as far as our knowledge of the variations of secretory 

 glands goes the variation of this milk, fall in well with the sec- 

 retory hypothesis to account for these solids. 



THE MEADOW PLANT BUG. MIR1S DOLABRATUS* 



(1) Miris dolabratus has been a conspicuous insect in 

 timothy meadows in portions of the eastern United States dur- 



*This is an abstract of a paper by Herbert Osborn, Consulting En- 

 tomologist, having the same title and published in the Journal of Agri- 

 cultural Research, Vol. XV, No. 3, pp. 175-200. Oct. 21, 1918. 



