DAIEY FARMING DAIRYING. 573 



gestetl by wliich the phenomena observed in these experiments may be inter- 

 ])retecl in tornis of genetic factors. 



Size inheritance in rabbits, E. C. Macdowell (Carnegie Imt. Washington 

 Pub. 1D6 (IDlJf), pp. 55, figs. 9). — The author explains the theory and gives 

 examples of multiple factors. In experimental work upon rabbits in which 

 comparatively small and large races were crossed a study was made of skeletal 

 measurements and of adult weight, from which observations it was concluded 

 that " whether on the basis of the comparison of the ranges of litters of the 

 first filial generation with those of their corresponding back crosses, or whether 

 on the basis of the relative vai'iability of the two generations as shown by the 

 standard deviations of the coefficients of size, or by the distribution of fre- 

 quencies in relation to the parents or grandparents, or, finally, by their body 

 weights, there is found a consistently greater diversity of sizes in the back 

 cross than in the first hybrid generation. Characters occur among the second 

 generation that are smaller than the corresponding characters in the small 

 parent ; others that are above the modes of the first generation large parents." 



The general law is stated as follows: " The second generation of a size cross 

 shows greater diversity than does the first generation or the parental lines. 

 Size characters that are inherited in a Mendelian fashion are included in the 

 above statement." 



An extensive bibliography is included, and a prefatory note and appendix by 

 W. E. Castle. 



Oyster propagation observations for 1913, J. Nelson {yew Jersey Stas. 

 Rpt. 1913, pp. 4S0-53Jf, pis. 6). — ^These studies include the usual climatic data 

 as to the amount of sunshine and rain, temperature, and winds, and observations 

 on the temperature and saltness of the water, and the tidal ebb and flow, the 

 progress of spawning by the oysters, the distribution and rate of growth of the 

 embryo or larval oysters ("fry"), and the setting of the spat (E. S. R., 30, 

 p. 374). 



DAIRY FARMING— DAIRYING. 



Beport of dairy husbandman, A. S. Cook (New Jersey Stas. Rpt. 1913, pp. 

 293-333, 355-365, pis. 3). — Two lots of eight cows each, of practically uniform 

 weight and production, were fed by the reversal system for two periods of 40 

 days each (10 days preliminary feeding intervening) on the following daily 

 rations : Lot 1, an average of 3.42 lbs. of soy-bean meal ; lot 2, 3.44 lbs. of cotton- 

 seed meal, in addition to the regular basal ration of oats and pea hay. alfalfa 

 hay, silage, green feed, beet pulp, and corn-and-cob meal, both lots receiving prac- 

 tically the same total amount of nutrients. 



The production of milk was practically the same on each ration, there being 

 a difference of only 275 lbs. in favor of cotton-seed meal in the entire period. 

 The soy-bean ration produced 27.7 lbs. more of milk fat than the cotton-seed 

 meal ration. The weights of cows during the experiment had the same uniform- 

 ity as the milk produced, there being a difference of only 100 lbs. in favor of 

 cotton-seed meal in the total weights of the two groups. 



" The cost of milk was 2.2 cts. per quart on the cotton-seed meal ration and 

 2.3 cts. on the soy-bean meal ration. Results of this experiment indicate that 

 when the price of cotton-seed meal is $33 [per ton] the dairyman can afford to 

 pay $41 for soy-bean meal." 



The average yearly milk yield for the 33 cows in the station herd was S,547 

 lbs. per cow, the average milk fat yield 319.1 lbs; the average cost of roughage, 

 figured at market price $61.81, or when figured at the cost of production $34.56; 

 the average cost of grain $51.54 ; the average profit with milk at 5 cts. per quart 



