New Britain herald., 1930-09-23
California Institute Given Results of Special Study Two Microscopic Qual-
 ities of Body Structure
 Probably Influence Male
 and Female Choice.

Pasadena, Cal, Sept. 23 R-A discovery indicating how nature de- termines whether sex shall be rlale or female was reported to the Ma tional Academy of Sciences today by Dr. Calvin B. Bridges of California Institute of, Technology.
 The method is a matter of bal Rnce between male and female ele- ments in body cells, and differs from many scientific findings which credit sex control almost wholly @ to two specialized microscopical particles in bodily cells. '
 Other Features Important
 In pr. Bridges studies these two particles are not alones They still exercise a large part of the control, but other particles which are known mainly to control other bodily char acterizations such as eye color and shape, also have small degree Of sex determination. It is the sum of them all that fixes the result.
 Dr. Bridges work was done on fruit flies. While he made no con- ment on possible human applica- tions, his findings increase the con- plexity of controlling sex, making 1t appear more remote than ever that man may learn how to fix in ad- vance the sex of his children.
 The control particles are chromo- somes, minute, threadlike bodies in cells, identified by many scientists in thousands of tests, as determin- ing hereditary characteristics of plants and animals.
 Chrom osomes, given the names of x and ', usually have been credited with determining sex by the way in which they combine. For example, in many cases a animation of two x chromosomes results in females and an x and Y combination in males. Dr. Bridges theory is one of genie balance" in which the other chromosomes also play a part in sex. ....
 Bred Thousands Of Flies
 The evidence he presented was ob- tained from breeding thousands of fruit flies having a chromosome combination that had not been known previously to produce any thing except males. He obtained some females by breeding process that dropped out some of the chrom- osomes controls. 9 This upset the genie balance in favor of the fe- males.
 Some flies developed patches on their bodies which were distinctively female, such as absence of combs that characterize the males.
 Dr. Bridges said this balance ex- tends to all hereditary characteris- tics, such as the length of wings and size of bodies. Some parts oi the chromosomes controlling wings tend to make long ones and other part short ones, so that the length becomes finally a balance between the two.
 New calculations on what happens to radio waves in the atmosphere 5C miles or more above the earth were presented by Dr. P. s. Epstein ol California Institute of Technology.
 Ionked Air Layer
 At that height is a layer of ionized VI and account for them travelling around the earth instead of shoot ing off entirely into space. Thls layer is electrically conductive.
 When conductivity of such a layer is low he finds that radio and other electrical waves should be reflected back. In some conducting medium' +hov shoI,ld he ahSorha6 entirely Some types of fading might be ex plained in this manner he said. bu added 1t is probable radio fading comes from other causes.
 The ionized refecting blanket rise! and falls, higher in day than a night, and higher in winter than 1T summer.
 Turbulence of the atmosphere i believed to affect it.