February 6, 1914] 



SCIENCE 



215 



fend in cold blood ; thus (p. 19) " even the 

 destructive bacteria which are killed by the 

 Bun probably enjoy an exquisite shudder in 

 the process which more than compensates 

 them for their extinction " ; and (p. 344) 

 "every step which he [the house-fly] takes he 

 plants a few dozen microbes, which include 

 those of infantile diarrhosa, typhoid and other 

 prevalent diseases," — a gross exaggeration in 

 a chapter which very properly calls attention 

 to the great harm done by flies as carriers of 

 bacteria. 



The time has certainly come for scientific 

 men in America to attack the problem of sci- 

 entific journalism in an organized and delib- 

 erate manner. The individual naturalist is 

 more or less helpless. When I was curator of 

 the museum in Jamaica I contributed weekly 

 articles to the newspapers of Kingston, which 

 printed them as written, and even illustrated 

 them when requested. These articles inter- 

 ested a good many people and were the cause 

 of many visits and contributions to the mu- 

 seum. In Colorado I have tried the same 

 thing, and given it up in despair. The papers 

 will not print things accurately or in full, and 

 will often supply headlines of the most ri- 

 diculous kind. Here is a tjrpical incident. 

 A friend of mine shot a large eagle and 

 measured it from tip to tip of the wings. 

 Thinking the matter of interest, he handed 

 in the item to a daily paper. The editor, 

 with the best of intentions in the world, 

 added a foot to the measurement, with the re- 

 sult that my friend appeared to those who 

 knew anything of eagles a remarkable liar! 

 These troubles are not confined to the wild 

 and woolly west. Even the Outlooh, certainly 

 one of our best-edited journals, recently pub- 

 lished an article on A. E. Wallace which con- 

 tained in the first column a number of errors 

 concerning the best-known facts of his life. 



It is not true, of course, that the news- 

 papers always select incompetent writers on 

 scientific subjects, or always distort accurate 

 information communicated to them; but if 

 they are to be the means of enlightening the 

 public concerning the discoveries of science, 

 they must never do these things, except 



through such imfortunate accidents as can 

 not perhaps wholly be avoided. One can not 

 vsrrite to the papers if the chances are one in 

 five or ten that one will be exhibited as a fool 

 or liar, and the public misled as to the facts. 



T. D. A. COCKERELL 



SPECIAL ARTICLES 



A NOTE ON SEX DETERMINATION^ 



Of the many hypotheses that have been ad- 

 vanced to explain the determination of sex, one 

 group seeks to show that in bilateral animals 

 the sex of the offspring is dependent upon the 

 right or left source of the effective genital 

 element in that right glands produce offspring 

 of one sex, left glands those of the other. Such 

 a general theory may be applied, of course, to 

 either the ovary or the testis. Thus Seligson 

 (1895)2 formulated the hypothesis that in 

 mammals the right ovary gives rise to eggs 

 that produce male ofl'spring, the left to eggs 

 that produce female offspring. 



In collecting a body of data to show the re- 

 lation of the size of litters to the number of 

 nipples in swine (Parker and Bullard, 1913),^ 

 certain facts appeared which have a bearing on 

 such hypotheses. The records brought together 

 in this connection included the position that 

 the young pigs occupied in the uterus and their 

 sex. In reasonably large litters it was there- 

 fore possible to make a rough comparison of 

 the products of one ovary with those of the 

 other by contrasting the young pigs in one 

 horn of the uterus with those in the other. 

 The possibility of the migration of an egg 

 from one side of the body to the other could 

 not be excluded, but to reduce to a rninimum 

 the effect, of this on the statistics and to make 

 the comparison as striking as possible, the 



1 Contributions from the Zoological Laboratory 

 of the Museum of Comparative Zoology at Har- 

 vard College, No. 245. 



- Seligson, E., ' ' Zur Bestimmung und Entstehiing 

 des Geschleehts, " Centralbl. fiir Gyndkol, Bd. 19, 

 pp. 590-595, 1895. 



3 Parker, G. H., and C. Bullard, ' ' On the Size of 

 Litters and the Number of Nipples in Swine," 

 Proceed. Amer. Acad. Arts and Sci., Vol. 49, pp. 

 397-426, 1913. 



