AGRICULTURAL BOTANY. 229 



cutiii. The author claims that throu;^h the irritation produced by the fungus 

 there is a response which results in a chemical change in the nature of the 

 product. 



Studies on the development of bulbous plants, G. Andr6 (Campt. Rend. 

 Acad. 8ci. [Paris], 150 (1910), Nos. 9, pp. 5Ji5~5Jf7 ; 11, pp 713-715).— A report 

 is given on the variation in dry matter, ash, total nitrogen, and the other con- 

 stituents of •bulb-forming plants at different stages of their growth. Most of 

 the oxi)eriments were made with onions, of which 100 of equal size and weight 

 were selected for study. Of these 20 were analyzed and the remainder planted 

 April 13. At intervals of a month or 6 weeks 20 of the onions were lifted and 

 analyzed, the last two periods being when the plants were in full flower and 

 when they had matured. 



There was found to be a loss in the fresh weight of the bulbs immediately 

 following planting, but this was subsequently changed into an increase in both 

 fresh and dry material, until at the time of flowering a maximum was reached 

 for both the aerial and subterranean parts of the plant. From the flowering 

 period until maturity there was a gradual reduction both in fresh and dry 

 weight of all parts of the plant, showing that there was a continuation of the 

 respiratory function of the plant until its maturity. 



In studying the increase in ash, nitrogen, etc., it was found that there was 

 a tranfer of nitrogen, phosphoric acid, and other constituents from the bulb 

 to the aerial plant immediately after the bulbs were set in the soil. This 

 transfer was later followed by increases when the plant growth had become 

 well established in the ash, total nitrogen, phosphoric acid, lime, magnesia, and 

 potash in both the bulbs and aerial parts of the plants. 



Winter condition of lenticels, L. A. Kenoyer (Trans. Kans. Acad. Sci., 22 

 (1909), pp. 323-326).— The author has investigated the claim that lenticels are 

 usually closed during the winter by the suberizatiou of the last layers of cells 

 and opened again when spring activity is resumed. He conducted a series of 

 experiments with twigs of 35 different species of plants, using the pressure of 

 a mercury column to force air through the twigs. 



Of 100 twigs tested, 65 seemed to have some or all of the lenticels open for 

 respiration during the winter mouths. It was noticed that the 2-year-old 

 growth had genei'ally more open lenticels than the growth of the season and 

 that the .3-year-old growth had more than that of 2 years. It was also observed 

 that in some species some twigs gave positive results while others gave negative 

 when tested. 



Examinations were also made for lenticels on the roots of several species 

 and they were found developed on many but not all. Their structure was quite 

 similar to that of lenticels occurring on the stems. Of 12 species of roots 

 examined. 4 were found with open lenticels and 8 without. In several instances 

 the root lenticels were found to be closed while those on the stems of the same 

 plants were open. 



Effect of various g'ases and vapors upon etiolated seedlings of the sweet 

 pea, L. I. Knight, R. C. Rose, and W. Crocker (Abs. in Science, n. set:, 31 

 (1910), No. 799, pp. 635, 636). — Various investigators having shown that the 

 impurities of laboratory air have a marked effect on etiolated seedlings of 

 \arious leguminous plants, the authors have studied the effect of gases and 

 vapors upon sweet pea seedlings. The effects of the gases are shown in de- 

 crease of rate of growth, in length, and in swelling and a horizontal placing 

 of the region of growth. 



About one dozen different kinds of gas and vapor were tested, and the effect 

 on Inhibition of growth, swelling, and horizontal placing is shown. Ethylene 

 gas at the rate of 0.1 part in 1 million of atmosphere was found to cause a 



