202 EXPEEIMENT STATION EECORD. 



hydrogen peroxid than in water. This suggests that the method may serve the 

 by a low percentage of germination, requires a longer time for germination in 

 hydrogen peroxid than in water. This suggests that the method may serve the 

 purpose of discriminating between doubtful and good seed." 



The water content of sprouts, roots, and stems after separation from the 

 embryo, 48 hours after germination, was found to range from 84.8 to 90.17 per 

 cent (average 87.75 per cent). The moisture content of soalied grain was less 

 than that of germinated grain, the most striking increase taking place in the 

 embryo. The percentage increase in the germinated grain can not be all 

 attributed to imbibed water, and in all probability is due to the production of 

 metabolic water. In the case of mature plants, wilting is in part produced by 

 the abstraction of water from the leaves, which is needed for the hydrolytic 

 processes which are going on iu the plant during sunshine. 



Tubers and bulbs when stimulated to sprouting produce moisture as a result 

 of dehydration and oxidation processes, to an amount much greater than was 

 originally present in the tuber or bulb. The most water is present in the 

 sprout. A similar process occurs in fruits. Immature seeds when exposed to 

 the air for a time can be made to germinate. The lack of germinating power 

 in the original seed as picked is due to the fact that certain necessary specific 

 enzyms are not present. The theoi-y of Naegeli in regard to the nature of 

 imbibition in plants is criticised. " It seems far simpler to account for the 

 phenomena of imbibition by a direct molecular combination of the substances 

 composing the tissues of organized bodies and water, than by assuming the 

 existence of micellae, the structure and form of which can not be demonstrated." 



Seeds when immersed in water generate a certain amount of heat which is 

 due to the union of the starch with water. When sprouting begins it is due 

 to the oxidation of sugar. "The final ripening changes iu most fruits proceed 

 fully as rapidly after removal from the tree as when left undisturbed. These 

 changes are the result of direct respiration of living cells in the fruit which 

 continue to function after the fruit is picked. The increase in succulence 

 during ripening is partly due to the production of metabolic water through 

 respiration and partly to the increased solubility of the products formed. It 

 is not due to water derived from the parent plant. . The water content is pro- 

 portionately .gi-eater in ripe fruit than in green fruit, in spite of considerable 

 loss of water through evaporation, even though the fruit be ripened off the 

 tree." 



With many animals the most of the water required in their metabolism is 

 derived from the oxidation of organic nutrients. "Many varieties of insects 

 and other animals that excrete the waste products of protein metabolism as 

 salts of uric acid in solid form require no free water at any time, except the 

 small amount present in air-dried food, the water content of which is usually 

 less than 10 per cent. This is possible becaiise the insoluble nature of uric 

 acid renders it but slightly poisonous and permits of its excretion with a mini- 

 mum loss of water. This is the case with the clothes moths, the grain 

 weevils, the bee moth, and a large number of insects that live upon air-dried 

 food throughout every stage of their development. The larvae of these insects 

 contain from 5 to 10 times the amount of free water contained in their food. 

 Some of these inscH^ts are capable of living long periods upon dry food in 

 an atmosphere containing no moisture. No doubt they would live indefinitely 

 upon dry food if this could be supplied without exposure to dry air which 

 enormously increases the loss of water by evaporation." 



Contribution to our knowledge of plant phosphatids, V. Njegovan {Hoppe- 

 Seyler's Ztschr. Physiol. Chem., 76 {1911), No. /, pp. 1-26; nhs in Zrnthl. 

 I'Jiysiol, 25 {1911), Nu. 26, pp. 1222, 1223; Zentbl. Expt. Med., 1 {1912), No. 2, p. 



