ANIMAL PRODUCTION. 871 



It is the opinion of the author that " the difference between the secondary 

 sexual characters of the sexes can not be ascribed solely to the internal secre- 

 tions, but that the genetic basis of each character must also be taken into con- 

 sideration. At least four groups of characters can be recognized : Head fur- 

 nishings, dependent in the male upon the testes, in the female independent of 

 the ovary in certain respects, in other respects dependent ; spurs independent of 

 testes, but on which the ovary exerts an inhibition, often incomplete; voice 

 and behavior, which in the male is partially dependent and partially inde- 

 pendent of the testes, yet closely correlated with these ; and plumage, which is 

 independent of the male organs, but on which the ovary exerts a modifying 

 influence. 



" Since the male may be feminized, it follows that if the ovary be consid- 

 ered an inhibitor merely, then the male must possess both potentialities for the 

 secondary sexual characters and that the ovarian secretion suppresses the male 

 character, allowing the female plumage to develop. Genetically, then, the male 

 secondary sexual characters must be considered dominant to tlie female. On 

 the other hand, if the ovarian secretion be considered a modifier, transforming 

 the male character into the female, we need not assume that both potentialities 

 exist in the male, but only the one. We may also make a similar assumption 

 for the normal female. At present it is impossible to determine whether or not 

 the ovarian secretion is an inhibitor or modifier." 



The feeding of young cMcks on grain mixtures of high and low lysin con- 

 tent, G. D. BucKNER, E. H. NoLLAU, and J. H. Kastle {Kentucky 8ta. Bui. 197 

 (1916), pp. 3-21, figs. 16; Amer. Jour. Physiol., 39 {1915), No. 2, pp. 162^171, 

 pi. 1). — Two lots of chicks were fed eight weeks, lot 1 receiving a mash twice a 

 day, morning and evening, consisting of equal parts by weight of finely ground 

 wheat, wheat bran, sunflower seed, and hemp seed, moistened with sour skim 

 milk, and once a day at noon they were given a coarsely-ground grain mixture 

 of wheat, hemp seed, and cracked corn. Lot 2 received a mash consisting of 

 finely-ground barley, rice, hominy, and oats, 100 gm. each, and 56 gm. of gluten 

 flour, and prepared with protein-free milk, and at noon a mixture of equal 

 parts of barley, rice, and hominy. The lysin content of the ration fed to 

 lot 1 was 3.8 per cent of the total nitrogen for the mash and 2.23 per cent 

 for the grain; lot 2, 0.5 per cent for the mash and 0.79 for the grain. 



Five of the chickens of lot 1 at the conclusion of the experiment weighed 

 2,553 gm., whereas 7 chickens in lot 2 weighed 1,195 gm. There were marked 

 differences in the feathering of the two lots of chickens, lot 1 showing the 

 feathering characteristic of the mature chicken, whereas lot 2 still showed 

 the feathering of the young and immature chick at the conclusion of the ex- 

 periment. Great difference in the two lots of chickens was also shown in their 

 general activity during the progress of the experiment, the chickens of lot 

 1 being greatly more active than the chickens of lot 2. It was also observed 

 that the chickens of lot 2 consumed more charcoal than the chickens of lot 1. 



It is stated that the desire showed by the young chick for hemp seed is re- 

 markable. It has been observed that out of a grain mixture containing this 

 material they will pick out every hemp seed before eating the remainder of 

 the ration. Of all the substances used in the feeding experiments hemp seed 

 is richest in lysin. 



The lots were then reversed, the chickens of lot 2 receiving the ration of lot 



1 and lot 1 the ration of lot 2. At the end of a week the chickens of lot 



2 were found to weigh 1,539 gm., an increase in seven days of 41.2 gm. per 

 chick, as compared with an average gain per week of 15.9 gm. during the 

 regular period of the experiment. It is stated that this rapid increase in 



41852°— ?so. 9—16 6 



