298 HOW CROPS FEED. 
No, 2, fed with uric acid, was the best developed plant 
of the series. At the conclusion of the experiment, it 
bore ten vigorous leaves, six of which were fresh, and two 
but partly withercd. It was 14 inches high, and carried 
two rudimentary ears (pistillate flowers), from the upper 
one of which hung tassels 6 inches long. 
No. 3, supplied with hippuric acid, bore eight leaves, 
four of which were withered, and two rudimentary ears, 
one of which tasseled. Height, 12 inches, 
No. 4, with hydrochlorate of guanine, had six leaves, 
one withered, and two ears, one of which was tasseled. 
Height, 12 inches. The weight of the crops (dried at 
212° F.), exclusive of the fine rootlets that could not be 
removed from the soil, was ascertained, with the subjoined 
results. 
1 2 3 4 
Without Hippurie 
Nitrogen. Uric Acid. Acid. Guanine. 
Weight of dried crop, 0.1925 grm. 1.9470 grm. 1.0149 grm. 0.9820 grm. 
a bi sued, 0.1644 ‘“ 1725 “ 0.1752 “ 0.1698 * 
gain, 0.0291 “ 1.7745 “ 0.8397 ‘ 0.8122 “ 
We thus have proof that all the substances employed 
contributed nitrogen to the growing plant. This is con- 
clusively shown by the fact that the development of pis- 
tillate organs, which are especially rich in nitrogen, 
occurred in the three plants fed with nitrogenous com- 
pounds, but was totally wanting in the other. The rela- 
tion of matter, new-organized by growth, to that derived 
from the seed, is strikingly seen from a comparison of the 
ratios of the weight of the seed to the increase of organs 
ized matter, the former being taken as unity. 
The ratio is approximatively 
for No. 1, 1: 0.2 
fe 1: 10.2 
ee 8; I 4,8 
“ss “ 4 1 4.8 
