278 HOW CROPS GROW. 



moist cotton or sawdust, and if, when fairly sprouted, 

 the young plants have their roots suspended in water, 

 taking care that the seed and stem are kept above the 

 liquid, they will continue to grow, and with due supplies 

 of nutriment will run through all the customary stages 

 of development, produce abundant foliage, blossoms, and 

 perfect seeds, without a moment's contact of their roots 

 with soil. (See Water Culture, p. 181.) 



In plants thus growing with their roots in a liquid 

 medium, after they have formed several large leaves, be 

 carefully transplanted to the soil, they wilt and perish, 

 unless frequently watered ; whereas similar plants, started 

 in the soil, may be transplanted without suffering in the 

 slightest degree, though the soil be of the usual dryness, 

 and receive no water. 



The water-bred seedlings, if abundantly watered as 

 often as the foliage wilts, recover themselves after a time, 

 and thenceforward continue to grow without the need of 

 watering. 



It might appear that the first-formed water-roots are 

 incapable of feeding the plant from a dry soil, and hence 

 the soil must be at first profusely watered ; after a time, 

 however, new roots are thrown out, which are adapted to 

 the altered situation of the plant, and then the growth 

 proceeds in the usual manner. 



The reverse experiment would seem to confirm this 

 view. If a seedling that has grown for a short time only 

 in the soil, so that its roots are but twice or thrice 

 branched, have these immersed in water, the roots 

 already formed mostly or entirely perish in a short time. 

 They indeed absorb water, and the plant is sustained by 

 them, but immediately new roots grow from the crown 

 with great rapidity, and take the place of the original 

 roots, which become disorganized and useless. It is, 

 however, only the young and active rootlets, and those 

 covered with hairs, which thus refuse to live in water, 



