396 



The Journal of Heredity 



Alexander Graham Bell's study carried 

 the child through the first four years. 

 The general trend of the evidence is the 

 same in all cases, and in two of them the 

 mothers imder twenty make a better 

 showing than any others. Differences 

 in race and social status in various cities 

 are so great that any exact comparison 

 would be unprofitable. It is only 

 desired here to insist on the uniform 

 trend of the statistics, which indicate 

 very clearly one of the dangers of 

 delayed marriage. 



The uniform trend of the data pre- 

 cludes the idea that the death rate is 

 more influenced by the mother's intel- 

 ligence than her age. It might be, 

 however, that it is largely influenced by 

 poverty. In this view the young 

 mothers would succeed better with their 

 children because they had only a few to 

 care for; while the mothers at the age of 

 35 to 40 had already large families and 



too little income to provide the new 

 arrivals with the necessary care. This 

 argument doubtless holds good to some 

 extent in the slums, but it can hardly 

 carry much weight in the Hyde family, 

 which seems on the whole to have been 

 fairly well-to-do. If both these in- 

 fluences (increasing experience and pov- 

 erty of mother with added age) were at 

 work, they would tend to neutralize 

 each other, thus leaving the actual 

 results to be attributed to physiological 

 factors connected with the age of the 

 mother. 



In sum, it seems clear that the age 

 of the mother at the birth of her chil- 

 dren has a marked influence on their 

 vitality; that as measured by infant 

 mortality the best age for a girl to 

 marry is probably between 20 and 25; 

 and that every year a woman delays 

 childbearing after the age of 25 is 

 penalizing her children. 



The Manchu Emperor K'ang Hsi as a Plant-Breeder 



One of the earliest examples of 

 successful breeding of a pure line, that 

 is, a uniform strain descended from a 

 single plant, appears to be furnished by 

 the Manchu emperor K'ang Hsi, who 

 reigned 1662-1723. The story (which, 

 of course, requires authentication) is 

 translated by E. R. Hue from the 

 emperor's own memoirs, as follows: 



"I was walk'ing, on the first day of the 

 sixth month, through some fields where 

 rice had been sown which was not 

 expected to mature until the ninth 

 month. I noticed, accidentally, one 

 rice plant which had already headed 

 out. It was much taller than any of the 

 others and was sufficiently ripe to be 

 plucked; I had it brought to me. The 

 grain of this head was well formed an.d 

 develoijcd; this gave me the idea of 

 saving it and ] planting it, in order to 

 see if it would retain its precocity the 

 following year; in effect, it did retain it. 

 All. the heads which appeared ri]:)ened 

 before the usual time and were ready 

 for harvest l)y the sixth month, i'^very 

 year has multiijlied the jjroduce of the 



preceding year, and for thirty years it 

 is the rice which has been served on my 

 table. Its kernel is elongated, and 

 slightly reddish in color; but it is of a 

 delightful odor, and of a very agreeable 

 savor. It has been named 'yu-mi,' 

 imperial rice, since it was first cultivated 

 in my gardens. It is the only variety 

 which will ripen north of the great wall, 

 where the cold stays late and comes 

 extremely early; and in the south, where 

 the climate is more mild and the ground 

 more fertile, two crops a year are easily 

 raised. It is indeed a sweet consolation 

 to me thus to have procured this ad- 

 vantage for my people." 



Hue {L' Empire Chinois, t. ii) further 

 states that the rice is particularly 

 adapted to semi-arid regions. This 

 x'ariety of rice, if it exists, has apparently 

 not been introduced to America. Cereal 

 experts have heard of a Manchurian 

 rice which corresponds in many ways to 

 K'ang Hsi's descri]Jtion, but it is held 

 in such esteem by its growers that they 

 have been imwilling to ])art wilh any 

 seed. 



