Doncaster: Determination of Sex 



277 



docs not seem to Dr. Doncaster to be 

 absolutely lacking. Certainly none of 

 the means so far suggested, some of 

 which have attained considerable notor- 

 iety, has any scientific standing, but 

 this does not prove that we may not 

 some time know more than we do now. 



On the basis of Dr. Doncaster's 

 hypothesis, it is obvious that control 

 of sex might be possible in one of two 

 ways: either by seeing that the child 

 received the proper chromosomes at 

 conception, or by finding some influence 

 which would act on the embryo after 

 conception so as to modify the deter- 

 mination of the chromosomes, if it 

 were not what was desi'red. It is hardly 

 possible to conceive of a way in which 

 sex might be controlled by the first 

 means, and a solution is therefore 

 probably to be sought along the second 

 line suggested. 



While the male in the human species 

 carries the X-chromosome, and there- 

 fore shoiild determine the sex of the 

 offspring, there is some evidence to 

 indicate that the egg-cell also has an 



influence in determining the sex. So 

 far, attempts to take advantage of 

 this — e. g., by special diet for the 

 mother — have met with no success. 

 The idea that the right ovary produces 

 male eggs and the left one female- 

 producing eggs also rests on a very 

 slender foundation. When the huge 

 mass of evidence available is carefully 

 criticized, it becomes evident that at 

 present we have absolutely no knowledge 

 as to how any condition can so affect 

 the mother as to determine the sex of 

 her offspring; nevertheless in the light 

 of Dr. Doncaster's hypothesis "it would 

 follow that the search for means of 

 influencing the sex of the offspring 

 through the mother is not of necessity 

 doomed to failure." It cannot be too 

 strongly emphasized that at present 

 there is no means known to science of 

 controlling sex in the human species, 

 but it seems to the author still reason- 

 able "to retain an open mind and to 

 regard the control of sex in man as an 

 achievement not entirely impossible of 

 realization." 



Bud Selectioa in Apples 



One of the important projects in hand at the Illinois agricultural experiment 

 station concerns bud selection with apples. C. J. Crandall writes: 



"Under this project the effort is being made to ascertain whether there are dif- 

 ferences in value between buds taken from different portions of trees for purposes 

 of propagation. Buds were selected for testing this in three different ways: first, 

 on the basis of size; second, on the basis of the location on the tree; and third, 

 on the basis of location on the shoot or branch. All selected buds were measured 

 and described and then grafted on ordinary apple seedlings. The trees grown 

 from these buds have been planted in orchard form, and there are now living 

 1,395 trees. Annual growth notes are being kept up on all trees and it is proposed 

 to grow them to fruiting age before attempting to report on their behavior. I 

 can only say at the present stage of the project that there appear to be some 

 slight differences in favor of buds of large size, and in favor of terminal as con- 

 trasted with lateral buds." 



Hardy Peaches for Missouri 



Hardy peaches are being bred at the Missouri experiment station by crosses 

 between large fruited, purple twigged sorts including Elberta, Champion, Carman, 

 and the green twig sorts represented by Rise's Seedling and Snow. The work 

 with peaches has shown them to be self-fertile; therefore growers who plant only 

 one variety need not fear that they will not get a crop, although such_ planting 

 with apples, pears and many other fruits, largely self-sterile, would be disastrous. 



