528 EXPERIMENT STATION RECORD. 



As a result of the application of these salts, growth was retarded by the 

 humate compound and by the calcium carbonate, while the other two minerals 

 stimulated both root and aerial development. They also caused a marked 

 increase in the ash content of the plants, the increase being largely composed 

 of silica. 



The experiment is believed to show that hydrolyzable salts have a special 

 influence on plants aside from their value as mineral nutrients. The action of 

 the different salts will be favorable or retarding according to the compounds 

 used. 



The role of oxygen in the formation and destruction of red pigments in 

 plants, R. Combes {Compt. Rend. Acad. ,Sci. [Paris], 150 (1910), No. U), pp. 

 1186-1189). — A study was made of a number of species of plants the green 

 leaves of which become reddened late in the season and of those the leaves 

 of which are red in the early stages, afterwards losing this color, and normally 

 becoming green. 



There was found to be a loss of oxygen in connection with the disa{)pearance 

 of anthocyaniu. As a result of the studies it is claimed that when anthocyanic 

 pigments are formed oxygen is retained by the organs during the process of 

 their reddening, and that at this time there is an increased activity of oxidation 

 in these organs. When the pigments are disappearing the organs containing 

 them suffer a loss of oxygen. 



Physiological studies of Cuscuta, O. Gertz (Bot. Noiiser, 1910, Nos. 2, pp. 

 65-80; 3, pp. ill-lSH). — The main purpose of the investigation was to study 

 the conditions of the formation of haustoria. The effect of radium emanations 

 on the twining motion and on the formation of haustoria was also stn(lle<l. the 

 results showing that both these processes were completely checked by the 

 emanations. 



A full bibliography of the subject is given in the paper. 



The growth of certain molds in oil, H. Coupin {Compt. Rend. Acad. Sci. 

 [Paris], 150 (1910), No. 19, pp. 1192, 1193).— A report is given of studies of 

 about a dozen species of molds, in which the fungi were transferred from pure 

 cultures to cubes of carrot and after growth had started submerged in olive oil. 

 In practically every instance there was some growth on the carrot inunersed in 

 the oil, the mycelium in many cases, however, remaining short and differing 

 quite materially from the normal appearance. In most instances the fungi 

 remained sterile; in only a few cases were fruiting bodies formed. In general 

 the growth resembled these molds in water rather than in the air. 



Endotrophic mycorrhiza in certain fruit trees, V. Boulet (Compt. Rend. 

 Acad. Sci. [Paris], 150 (1910), No. 19, pp. 1190-1192).— The author reports the 

 occurrence of endotrophic mycorrhiza on the roots of almond, apricot, peach, 

 cherry, plum, prune, quince, pear, apple, etc., in various regions of France. 

 The mycorrhiza appears to live as a parasite and the parasitism generally has 

 a beneficial effect on the host, except when the essential organs of the root are 

 attacked. Under normal conditions they are protected by their vigorous growth. 



Hyphal fungi occurring in the root tubercles of Elaeagnus angustifolia 

 and Alnus glutinosa, F. Zach (Sit:::ber. K. Akad. Wiss. [Vienna], Malh. 

 Naturw. Kl., 117 (1908), I, No. 8, pp. 913-981,, pi. i).— This is a further study 

 (E. S. R., 16, p. 1095) and discussion of the symbiotic relationship and the 

 taxonomic position of the hyphal fungi found in the root tubercles of A. glut- 

 inosa and E. angustifolia. 



Structure of tomato skins, B. H. A. Groth (New Jersey Stas. Bui. 228. pp. 

 3-20, pis. 8). — This bulletin deals with the cell structure of the fruit skins of 

 nine types of tomatoes, and is a part of work now in progress on the histology 

 of stems, leaves, and roots of the same types. The object of the series is to 



