932 EXPERIMENT STATION RECORD, 



was made of the seeds of about 45 families of plants, in some cases many genera 

 and species being examined, to determine the presence of peroxidase, or, as the 

 authors designate it, peroxidiastase. The authors found from the examination 

 of a large number of seed that there is generally present a peroxidase in dry 

 seed, but that it does not continue indefinitely in the seed. There appears to 

 be a relation between the age of the seed and the presence of peroxidase, and 

 this is to be investigated further. 



The morphog'enetic action of certain organic substances on the higher 

 plants, M. MoLLiARD {Rev. Gen. Bot., 19 (1907), Nos. 222, pp. 21,1-291, pis 2, figs. 

 20; 223, pp. 329-3J,9, pi. 1, figs. 20; 224, pp. 357-391, pi. 1, figs. i2).— Experiments 

 are reported with radish, onion, morning glory, nasturtium, and cress seed- 

 lings grown in glucose and other carbohydrates and also in nitrogenous solu- 

 tions in open and closed tubes, in atmospheres enriched in carbon dioxid, and 

 under various colored screens to determine the effect of these external agencies 

 on the morphology and anatomy of the plants. 



The action of the different substances was found to have vei-y characteristic 

 effects on the anatomical structure of the plants. It was found possible to 

 secure a fleshy root development with radishes whenever there was present 

 in the culture medium an available amount of glucose or other carbohydrate 

 equal to the amount normally formed by the plant. Similar results were 

 obtained in the formation of bulbs on the onion seedlings. The flowers in the 

 radish and morning glory were abnormal under the influence of glucose. In 

 the latter flower buds were formed at the first nodes, but they did not develop 

 much further. The production of starch took place when the only source 

 of carbohydrates was from the glucose, levulose, etc., obtained through the 

 roots. In the presence of large amounts of sugars the leaves of the plants 

 underwent profound modifications, approaching in form and structure the 

 cotyledons. 



The effect of sugars and other organic substances on the formation and 

 structure of the woody tissues and the distribution of their elements is 

 described at length. The action of asparagin on radishes, especially in closed 

 tubes, showed a marked degeneration in the nuclear structures. 



Recent investigations on the role of hydrocyanic acid in green plants, II, 

 M. Treub (Ann. Jard. Bot. Buitenzorg, 2. set:, 6 (1907), pt. 1, pp. 79-106, pis. 

 2). — By reason of the statement of Guiguard (E. S. R., IS, p. 126) that hydro- 

 cyanic acid is abundant in fallen leaves of elderberry, the author has repeated 

 his investigations and has found that his previous conclusions were confirmed, 

 at least so far as tropical plants are concerned. 



The amount of hydrocyanic acid was in general most abundant in the very 

 young leaves, the proportion diminishing as the leaves grew older, and entirely 

 disappearing in many species when the leaves became yellow and were about 

 to fall. Only one species (Indigofera galcgoides) did not conform to this prin- 

 ciple, its leaves retaining practically all their hydrocyanic acid even when 

 fully mature. The diminishing amount of hydrocyanic acid is attributed to 

 a lack of the components yielding that substance and not to the disappear- 

 ance of the enzyms which act upon the glucosids. In general the more active 

 the leaf the more hydrocyanic acid it will contain. 



A description is given of the method adopted by the author for the detei-- 

 mination of the hydrocyanic acid occurring in plants and a list presented of 

 6 genera and 16 species not hitherto reported as containing hydrocyanic acid. 



Experiments are described which show the diminution of hydrocyanic acid 

 in plants after a prolonged sojourn in darkness and a gradual increase when 

 again brought into the light. Marked changes were noted after .5 or more 

 days in darkness and when a like period had elapsed after the plants were 



