470 EXPERIMENT STATION RECOED. 



animals belonged. Selection witliiu a race was without effect in producing a 

 new race. The fundamental constitution of the race appeared to be resistant 

 to all sorts of influences, changing only in rare instances and fur unknown 

 causes. Most differences between individuals were teui]>orary and were without 

 significance in inheritance. 



Heredity and variation in the simplest org'anisms, H. S. Jennings (Amer. 

 Nat., 43 (1900), No. 510, pp. 321-331, figa. 5). — This is a popular presentation 

 of the articles noted above. The work involved a study and measurement of 

 over 10,000 individuals of Paramecium kept under experimental conditions for 

 many generations. 



The advantages of unicellular animals for studying these problems is pointed 

 out. The survival of the fittest among many generations may be observed in 

 the course of a few days. " For studying heredity and vjiriation we get a 

 generation a day, and we may keep unlimited numbers of pedigreed stock in 

 a watch glass that can be placed under the microscope." 



Mendel's principles of heredity, W. Bateson {Camhridgc, IDO'J, pp. 

 XIV+396, pis. 0, figs. IJf). — The main part of this book contains a concise ac- 

 count of the discoveries in regard to heredity made by the application of Mendel's 

 method of research. The aim is to present concrete phenomena rather than 

 to discuss their bearing on the facts of biological problems, although a chapter 

 on biological conceptions and one on practical applications of Mendelian prin- 

 ciples have been included. Part 2 contains a bibliography of over 300 refer- 

 ences, a biogi-aphical notice of Mendel, and a translation of his two papers. 



The categ'ories of variation, S. J. Holmes {Amer. Nat., 43 (1909), No. 509, 

 pp. 257-2S-)). — This paper discusses the classification of germinal variations 

 recognized by De Vries. 



The author does not think these variations distinct, nor that the facts of 

 Mendelian inheritance compel us to adopt a particulate theory of heredity. 



" Neither the facts of variability nor those of Mendelian inheritance give 

 any support to the doctrine of pangens, determinants, or other assumetl bearers 

 of unit characters. Unit characters, as elements that can enter or depart from 

 the complex of tendencies that make up an organism, probably have no exist- 

 ence. It is evident that variations differ in their stability, but the explanation 

 of this fact may lie in the i)hysiological relations of the variation rather than 

 in some hypothetical representative unit." 



The colors of Highland cattle, J. Wilson (Sci. Proc. Roy. Duhlin fe'oc, n. ser., 

 12 (1909), No. 8, pp. 66-76, pi. 1, clgm. /).— From a study of a Highland herd 

 book the author arrives at the following conclusions : 



" There are four colors forming the basis of present-day Highland colors, 

 namely, black, blackish-brown or donn, i-efl, and light dun. One other color, 

 white, and other ' markings ' have been absorbed from time to time ; but these 

 have been almost entire^ bred out. The reds may be of several shades, but 

 there are not sufficient data to separate them. Black is the dominant of red. 

 Black produces dun hybrids — registered ' dun,' ' dark dun,' etc. — when mated 

 with light dun. Donn or blackish-brown produces brindle hybrids when mated 

 with black, red, and light dun. Red produces yellow hybrids when mated 

 with light dun. . . . These conclusions are not put forward as absolute cer- 

 tainties, but as conclusions for which some further confirmation is not unde- 

 sirable. It is hoped that breeders of Highlanders, Longhorns, and Jerseys may 

 give closer attention to shades and markings when registering their stock, and 

 so we shall acquire more accurate data." 



Does telegony exist? S. F. Morse (Country Gent., 7^ (1909), No. 29U, P- 

 6-'f0). — The author discusses the evidence presented from various sources on 

 the alleged influence of a previous sire on the progeny, and draws the conclu- 



