378 EXPERIMENT iSTATION RECORD. 



Some effects of external conditions upon the white mouse, F. R. Sttmneu 

 (Jour. Expt. Zooi., 7 (IDO!)), .Vo. /, />/>. Ul-IO'). figs. l.)). — An inquiry into the 

 t'ffect of dillVrenecs of tomponilure and iiuiiiidity upon the post-natal develop- 

 ment of the white mouse, the primary object beiuf;; to test the (luestion of th(? 

 transmission of certain characti'rs, is reported. ITp\A'ards of 400 individuals 

 were used and the results showed that different temperatures operatinji tlu-ongh- 

 out the period of jirowth did affect the dimensions of the tail, foot, ear, and 

 probably hair. The tails of mice Icept in a warm room were from VI to over 

 .■?() per cent longer than tliose from mice kept in a cold room. Tlie moditications 

 thus artificially produced are such as have long been known to distinguisli 

 nortliern from southern races of mammals. 



The reappearance in the offspring of artificially produced parental modi- 

 fications, F. B. SuMNicR {Anivr. Nat., J/'f {1910), No. Gil, pp. .5-18, fig-s. 2). — 

 The offsiiring of the mice used in the experiment noted above were measured 

 in order to determine quantitatively the effect of temperature on the next 

 generation. It was found that the modifications of tlie parent persisted to 

 some extent in the offspring. The author suggests several explanations which 

 might account for these results and among others the possibility of the inherit- 

 ance of acquired characters. 



What basic principles of breeding are established by the methods prac- 

 ticed in England in the improvement of live stock? L. Hoffmann (Arh. 

 Dent. (JtstU. ZiiditHiigsl;., IDO'J, No. Ji,pp. IV+150). — A description of the breeds 

 of live stock which have originated in England and an account of the methods 

 used by English breeders which led to their improvement. 



Hornless cattle, J. C. Ewakt {Live Stock Jour. [London], 70 {1909), No. 

 1861, pp. 599, 600). — The author refers to various theories that account for the 

 origin of hornless cattle. Recent explorations in Turkestan and records from 

 Babylonia lend support to the view that the same conditions which are thought 

 to have reduced Bos tuiinis in size also caused the i-eversion to the ancestral 

 hornless type. 



The inheritance of horns and face color in -sheep, T. B. Wood {Jour. Agr. 

 ScL, 3 {1909), No. 2, pp. Upj-lo'i, pis. Jf). — A study of Mendelian inheritance 

 with crosses between Dorset Horn and Suffolk sheep. 



The Iambs of the first generation were identical whichever way the cross 

 was made. All had speckled faces and legs. The rams showed horns im- 

 mediately after birth, and in the ewes small scurs were formed on reaching 

 maturity. In the second generation 7 rams had large horns, 7 round scurs, 

 3 loose scurs, and 4 no scurs, whereas of the ewes, 8 had no horns, 3 had large 

 horns, and 1 round scurs. The distribution of face color was as follows: Three 

 with pure white faces, 3 with pure black faces, 3 with white faces and black 

 noses, 3 with white faces and black round the eyes, 3 with white faces and 

 black on both eyes and nose, 1 with large irregular patches of blacli on the 

 face, and 17 with more or less uniformly speckled faces. 



These and subsequent notings show that horns are dominant in the male and 

 recessive in the female. Neither the white nor the black face appears to be 

 dominant. The black face is not a simple character. Woolly and bare heads 

 appear to be a pair of characters which blend in the first cross but segregate 

 again in later generations. There are a number of instances of recombination 

 such as horns, woolly poll and face, and black face. Another example is the 

 bare head and hornless character of the Suffolks combined with the white face 

 of the Dorsets. 



A difficulty encountered in these experiments was the slowness and lack of 

 certainty in testing the females and the complicated nature of what were 

 thought to be simple characters. Points of economic impoi'tance such as would 



