652 



EXPERIMENT STATION RECORD. 



and determine its occurrence, and the meaning of the physiological events that are 

 associated with it. 



In the investigations the tips of growing roots, especially seedlings, were injured 

 in various ways by making incisions into the region about the apex, and the reac- 

 tions were carefully examined and compared. The work suggests a number of 

 important problems for future investigation, and contains an extended bibliography 

 of literature relating to the subject. 



The absorptive capacity of roots in the light and in the dark, E. Pantanelli 

 (Landw. Jahrb., 34 (1905), No. 3-4, pp. 665-683). — Seedlings of various plants, includ- 

 ing Zea until*, were placed in the dark and also in the light to determine the influ- 

 ence of darkness upon the absorptive capacity of the roots. 



It was found that when the seedlings were kept in the dark the roots took up 

 absolutely less, but relatively more, salts than water, while in the light the reverse 

 took place. When the stems and leaves alone were exposed to the light the roots 

 absorbed more water while the salt absorption was relatively decreased, but 

 when the roots alone were subjected to the action of light they took up more salt 

 than water. These resultsare regarded as indicating that the use of mineral substances 

 by the plant is not regulated by transpiration alone, and that the roots have the 

 power of changing the relation of salt to water absorption according to conditions. 

 The selective capacity of the living organism manifests itself in such cases. 



A study of the injury to plants by fumes from industrial works, P. Sorauer 

 {Landw. Jahrb., 33 (1904), No. 4-5, pp. 585-664, pis. 4)-— The results are given of a 

 prolonged study of the effects of fumes from industrial works, especially the effects 

 of chlorin and hydrochloric-acid fumes, on wheat, oats, and barley. 



The author describes at length the various anatomical changes observed in these 

 different plants wherever any departure from normal structures was noted. These 

 include changes due to ripening, injury, fungi, overfertilization, superabundant 

 water, etc., comparisons being made with injuries attributed to noxious fumes and 

 with the changes experimentally produced upon the plants under observation when 

 exposed to chlorin and hydrochloric-acid fumes. 



Summarizing his observations, the author says that the injuries due to fumes differ 

 only in degree from those observed on similar plants not subjected to the influence 

 of gases. The distinction between injured and uninjured plants is a quantitative one, 

 and can only be determined by comparisons with similar plants grown in regions 

 known to be free from injurious fumes. 



Pot experiments to determine the limits of endurance of different farm 

 crops for certain injurious substances, F. B. Guthrie and R. Helms (Agr. Gaz. 

 N. S. Wales, 16 (1905), No. 9, pp. 853-860).— Pots were rilled with a rich garden loam 

 mixed with a nearly equal quantity of light sand and fertilized with 10 gm. of super- 

 phosphate. To these pots were added different quantities of sodium chlorid, 

 sodium carbonate, sodium chlorate, and arsenious acid, and the effect on the germ- 

 ination and growth of barley and rye was observed. The results obtained are shown 

 in the following table: 



Effect of different percentages of injurious substances in the soil on the germination and 



growth of barley and rye. 



