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BOITLE-NECKED AND ORDINARY EURKkA LEMONS 



A limb-sport was found in a lemon tree, which gave rise to lemons of the peculiar shape shown 

 at the top of the photograph. The effe.t of the change was not confined to the fruit, but 

 extended also to the leaves, which are much narrower than ordinary. Normal fruit and 

 leaves, borne by the unchanged part of tree, are shown at the bottom of the photograph. 

 The marked change in leaves and fruit is a good illustration of the fact that variability is 

 correlated, and that one part of an organism cannot be markedly changed without producing 

 changes in various other parts. (Fig. 8.) , 



The Number of Unmarried Persons in the United States 



There are 17,000,000 celibates in the 

 United States, according to a statement 

 which has been goinj^ the rounds of 

 the ])ress, after originating in a maga- 

 zine article on the sex question. Ex- 

 aminatif)n of the census schedules for 

 1910 indicates that this figure includes 

 all males over 20 and all females over 15. 

 A calculation based on such age limits 

 is misleading, but the actual facts are 

 quite striking enough. Persons 35 years 

 of age or over are relatively unlikely to 

 marry, and it seems fair to base compu- 

 tations on that age. They show, then, 

 that there are nearly 2,000,000 un- 



married men in the population, and 

 about 1,250,000 immarried women. 

 There are about 1,500,000 unmarried 

 women between the ages of 25 and 34, 

 and a considerable part of these are 

 certain never to marry. The celibacy of 

 these millions is, from a eugenic point of 

 view, not wholly to be deplored. While 

 the number includes many potential 

 fathers and mothers of a desirable 

 character it is probable that, on the 

 whole, the.sc life-long celibates are 

 eugenically inferior to the married 

 l)oi)ulation. 



Pure-lines of Bacteria 



From studies of bacteria. L. J. Cole 

 and W. H. Wright conclude that 

 descendants of a single cell constitute 

 a jnire-line, which cannot be modified 

 by selection. Mutations occur in such 

 lines, both s])ontaneously and in re- 



spouse to external stimulus. Much of 

 the variation in bacterial cultures is 

 attributable to isolation and perpetua- 

 tion of certain piu'e-lines and the elimi- 

 nation of others. The study is re|)orted 

 in Jour. Inject. Diseases, 19, pp. 209-221. 



