18 



The journal of Hi;rei)itv;' 



All of the Asiatic varieties of chestnut 

 so far known are small trees and prob- 

 ably slow growing. The Chinese chest- 

 nut, or at least the variety shown in 

 figure 1, bears nuts that are about the 

 size of the American chestnut, or a 

 trifle larger, and of a delicate, sweet 

 flavor and fine texture. The Japanese 

 varieties are also small trees and in 

 general have large, coarse nuts, with a 

 bitter adherent inner skin; but there 

 appear to be some strains that arc sweet. 

 No European varieties have yet been 

 found that are appreciably resistant. 

 Perhaps the greatest desideratum at 

 this time is a resistant tree of the forest 



type. But this may yet be found, as 

 the world-species of Castanea are not 

 yet assembled. 



How much easier it would have been, 

 and how much loss could have been 

 avoided if im]jortation of nursery stock 

 had been safeguarded in time to have 

 excluded this latest addition to our 

 collection of foreign diseases and pests. 

 Pre\'ention is. cheaper than cure; this 

 is the first great lesson to be learned 

 from the invasion of the chestnut bark 

 disease. It is too late to exclude this 

 undesirable citizen; but we can at 

 least redouble our efforts to see that no 

 others fjet a foothold on this continent. 



Inheritance of Milk Yield 



Inheritance of the property of milk production in a registered herd of cows in 

 East Prussia is discussed by J. Peters in Nos. 11, 12 and 13 of the Deutsche Land- 

 wirtschaftliche Tierzucht, Hannover, Germany, 1913. His data show great 

 variations in the inheritance of milk yield. The offspring of the best mothers 

 yielded, on the average, the most milk and those of the inferior mothers least. 

 The range of variation was not, however, so great among daughters as among 

 mothers. First class cows produced both good and inferior oft'simng, and vice 

 versa. The inheritance varied around a center, which was somewhat higher in the 

 daughters of superior mothers than in those of inferior cows. The magnitude 

 of the variation was the same for all classes. 



Peters then determined the milk production of the grandparents and of the 

 separate families of the herd. With regard to the families, he found that some 

 produced relatively many good animals, while the descendants of others were 

 usually inferior cows; in other families, again, he observed unusually large varia- 

 tions in the i^erformance of the offsjsring. As a rule, however, the oft'spring of good 

 families were good milkers and those of inferior families unsatisfactory. Inheritance 

 varied in the case of mediocre families. 



The writer comes to the conclu.sion that it is not stitricienl to estimate the absolute 

 and relative yield of cows, and upon these data to select the offspring of the best 

 individual jicrformers for further breeding, but it is necessary to select the best 

 families, for among the descendants of these will be found the largest number of 

 good milch cows. His data are summarized in the Bulletin of the International 

 Agricultural In.stitute, Rome. 



The Improvement of the Human Race 



The im])rovement of the breed of mankind is no insu])eral)le (liflieulty. If every- 

 body were to agree on the im])rovement of the race of man being a matter of the very 

 utmost imi)ortance, and if the theory of the hereditary transmission of ciualities 

 in man was as thoroughly understood as it is in the ease of our domestic animals, 

 I see no absurdity in supposing that, in some way or other, the improvement would 

 be carried into effect. — Francis Galton, in Maeinillan's Magazine (1865). 



