072 EXPERIMENT STATION RECORD. 



leuis could only Itc treated by the fourfold lahic iii'-ihod. wlik-li led to diverse 

 results according to the arbitrary placln.ijc of tlu> dlvlsitai. Several examples of 

 the method are giveu. 



A mechanism for organic correlation, G. II. Parker {Amer. Nat., ffS (1909), 

 No. .308, pp. .>l.i-21S). — The author cites examples to show that many organs 

 of the body itroduce hormones I hat affwt the form or structure of other organs, 

 external as well as internal. " .Shattock and Seligmann have shown [that 

 when! a small piece of a male gland is grafted into a young castrated male, the 

 comb, hackles, and spurs may develop as in a normal bird. It is, therefore, 

 highly probable that the reproductive glands, like the ductless glands, produce 

 hormones by which the development of the secondary sexual organs is deter- 

 mined." 



The author thinks that the hormones of the internal environment of an 

 organism are mechanisms of correlation and that by means of them one organ 

 influences another. lie points out that in nature selection may well be con- 

 ceived to modify an internal hormone-producing organ if this organ is of vital 

 significance, and incidentally to establish a new internal environment that would 

 so intluence the form and external configuration of a given organism that it 

 would be called a new species, even though none of the new external features 

 by which this organism would be described might show the least usefulness. 



The relation between fertility and normality in rats, R. E. Lloyd {Rec. 

 Indian Mils., 3 {li)()<)), No. 3, pp. 261-26.}). — The weight of 1,000 female house 

 rats of India ranged from 50 to 210 gm. Correlatit>n tables are presented which 

 do not show any correlation between size and fertility. The mode, or the num- 

 ber of young in a litter occurring with the greatest frequency, was five. 



The significance of the " chestnuts " on the legs of solid-hoofed mammals, 

 R. HiNTZE (Zool. Anz., 35 {1010), No. 12-13, pp. 312-380).— The author suggests 

 that the growths, commonly called chestnuts, which occur on the legs of the 

 horse and its allies, may have had their origin as the horny pads or cushions 

 of a plantigrade ancestor which became vestigial when the animal acquired the 

 habit of walking on its toes. 



Anatomical-histological investigations on the '' shield " of male swine 

 in regard to meat inspection, G. Stemmer iAnatoniiHch-histologi.sclic Untcr- 

 siidninyrn iibrr (l<n Scliihl dcr Mdnnlichcn i^iddrn niit Bcrucksichtigung dcr 

 Fleischbcschau. Inaug. Diss., Univ. Bern, 190!), pp. ol, pis. 3, figs. 3). — From a 

 study of a large number of animals the author concludes that the thickening 

 of the dermis which occurs on the shoulder, commonly called the shield, is a 

 secondary sex characteristic of males. It is a post-embryouic structure not 

 known in any other animal and consists chiefly of connective tissue. Accord- 

 ing to the German feeding stuff law it is not a human food and should be re- 

 moved from the slaughtered animal before stamping, although some butchers 

 are known to grind it uj) for sausage. 



The effect of castration on the metabolism, F. H. McCrudden (Jour. Biol. 

 Chem.. 7 (1910), No. 3. pp. 185-197).— A brief review by the author of the 

 literature on this subject does not show that there is any definite knowledge 

 concerning the effect of the removal of the testes and ovaries on metabolism, 

 although the general opinion is that there is at least a temporary change. 



The author also reports an experiment of his own in which 2 male and female 

 dogs were desexed and fed a ration of lean beef heart, lard, cracker dust, and 

 water. The results do not confirm the view generally held that castration is 

 followed by a retention of material, especially the mineral elements, the general 

 teodeucy being in the other direction. In almost eveij instance where there 



