366 EXPERIMENT STATION RECORD. 



Berlin and Vienna, 1910, pp. 82; FortscJir. Nattirw. Forsch., 2 {1911), pp. 1- 

 82). — A critical review and bibliography of recent work. 



The inheritance of color in Shorthorn cattle. — A study in somatic blends 

 acompanying gametic segregation and intra-zygotic inhibition and reaction, 

 H. H. Laughlin {Amer. Nat., Jf5 {1911), No. 540, pp. 105-1J,2, figs. 11; J,ij 

 {1912), No. 5/(1, pp. 5-28). — This article discusses the origin and inheritance of 

 coat color iu Shorthorns. 



From data gathered from various sources the author states that the single 

 unit coat color hypothesis, which does not explain the facts, should be replaced 

 by the following: "There are 2 gi'oups of genetically independent sets of 

 hairs intermingled to make up the Shorthorn color coat. One set is alternatively 

 'positive white' (W) and red (R), in which the white is dominant and the red 

 recessive; the other set is alternatively red (R) or ' albinic white' (wr), in 

 which the red is dominant and the white recessive. Dominant white is caused 

 by a specific antibody existing in the zygote in small quantities, retarding or 

 inhibiting the ontogenesis of the determiner for pigmentation. The same body 

 existing in larger quantities reacts with and destroys the determiner for pig- 

 mentation, causing recessive or albinic white." 



The dominant white of the Shorthorn is thought to be derived from the 

 Romano-British cattle, and the recessive white from the Dutch flecked, the 

 colored ai"eas of which took the differential coloring because they lacked the 

 positive graying factor. The spotted color pattern or coarse mosaic came in 

 with the Dutch bulls of the eighteenth century importation. 



In regard to somatic bleuds the author says : " Blends are essentially the 

 somatic aspects of the fortuitous combinations of the patent and latent phases 

 of two or more genetically independent units. In this sense Galton's law may 

 justly stand for the general measure of ancestral influence — a measure of the 

 operation of the laws of chance. The existence of somatic bleuds can not be 

 denied, for they are among the most definite things commonly observed in 

 inheritance. The more cursory the examination and the more general the view 

 of such cases, the more seeming the blend; however, a more minute inspection 

 often reveals the segregation of the parental factors, all of which points toward 

 the minuteness of the unit character and the purity of the gamete. Were blend- 

 ing in the commonly understood sense a fact, all individuals of a race or a 

 strain would in a few generations become identical with each other. It is the 

 creation of new units by intra-zygotic reactions and intra-gametic intrusions, 

 together with the segregation and recombination of the unaltered ultimate units 

 of inheritance that have given selection such an opportunity for developing so 

 many strains and species."' 



On the occurrence of fat in the epithelium, cartilage, and muscle fibers 

 of the ox. — On the histogenesis of the adipose tissue of the ox, E. T. Bell 

 {Amer. Jonr. An^at., 9 {1909), No. 3, pp. 401-438, pis. 2, figs. 13).— A study of 

 the nature of adipose tissue and the distribution of fat in the different organs 

 of the body of the fetal calf and of fat in steers. The work was done in con- 

 nection with that already noted from another source (E. S. R., 25, p. 273). 



Preceding the formation of adipose tissue was an opeu-meshed fibrillar con- 

 nective tissue, consisting of loosely arranged cells. " In the formation of a 

 fat lobule the cells adjacent to the blood vessel are filled with fat first. The 

 filling of the cells with fat extends from the blood vessel outwards in all 

 directions. This process is closely similar to the der>osition of fat in the liver 

 where it is deposited first in the cells immediately adjacent to a vein and later 

 into those lying farther out. 



" The branched preadipose cell becomes rounded by the accumulation of fat 

 in its interior. Its processes are absorbed. The cell membrane is differentiated 



