304 PHYSIOLOGY [Box. Absts., Vol. X, 



a wound stimulus, resulting from contact of one side of the coleoptile with silver nitrate or a 

 red hot glass rod, can be transmitted from a coleoptile tip, which has been amputated and 

 Bubsequently replaced upon the stump of a coleoptile, across the wound surfaces into the 

 basal part of the coleoptile. This was found to be the case even when the stimulated tip 

 and the stump were from different individuals of (1) the same species, (2) different species, 

 or (3) different genera, though in the last case positive results were not so frequently secured. 

 The material experimented with gave similar results when subjected to contact stimulation. 

 It was also possible to secure a tropistic curvature when a little fragment of injured tissue 

 from the same or some other species was placed eccentrically on the wound surface of a coleop- 

 tile stump. — R. M. Holman. 



TEMPERATURE RELATIONS 



1970. Weiss, H. The thermal death point of the spores of Bacillus botulinus in canned 

 foods. Jour. Infect. Diseases 29: 363-368. 1921. — The thermal death point of spores of 

 B. botulinus varies with the H-ion concentration of the particular food in question. The 

 more acid foods, such as canned fruits, require a maximum of 50 minutes at 100°, 30 minutes 

 at 105°, and 15 minutes at 110°C., but the majority of canned foods in this group require 

 much shorter exposures. The vegetable products, which are less acid and more nearly ap- 

 proach the neutral reaction, require from 90 to 180 minutes exposures at 100°, 30 to 70 minutes 

 at 105°, and 10 to 20 minutes at 110°C. — The thermal death point also depends on the con- 

 sistency of the particular food, on presence and concentration of syrup, size of can, size and 

 compactness of the cook, and the retort technic. — Selman A. Waksman. 



1971. Wright, R. C. Freezing and undercooling of Irish potatoes. Potato Mag. 4'': 14, 

 16-18. 1921. — Late varieties have lower freezing points, averaging 29.15°F. for the varieties 

 tested. Undercooling at 28°F. for 70 hoiirs, or at 25°F. for 19 hours, caused internal dis- 

 coloration, which was induced sooner by jarring, air currents, wetting, and rolling in bags. — 

 Donald Folsom. 



RADIANT ENERGY RELATIONS 



1972. Dacy, George H. Influencia de la luz en el desarroUo de las plantas. [Influence 

 of light on the growth of plants.] Rev. Agric. Tropic. [Salvador] 1:209-216. 1921.— This 

 is a review of the work of Garner and Allard (see Bot. Absts. 5, Entry 22) reprinted from 

 La Hacienda. — •/. A. Stevenson. 



1973. Walker, W. F., and R. W. Pryer. Bactericidal action of water treated by ultra 

 violet rays. Amer. Jour. Public Health 11: 703-706. Fig. 1. 1921. — Results are given which 

 show "that the exposure of water to ultra violet light emitted from a quartz mercury vapor 

 lamp, imparts to water a definite residual bactericidal property." — C. ^-l. Ludwig. 



TOXIC AGENTS 



1974. Peters, R. A. Variations in the resistance of protozoon organisms to toxic agents. 

 Jour. Physiol. 54: 260-266. 1920. — The results of experiments testing the toxicity of mercuric 

 chloride upon Colpidiwm plotted as the logarithm of the percentage of survivors gave a 

 straight line curve except a slight "kink" at the beginning. It is reasoned that this type of 

 curve is indicative of variations, of the organisms, in resistance to toxic agents. The study 

 of frequency curves and the logarithmic curve of the S-curve gives the chief data for the 

 argument. — Ernest Shaw Reynolds. 



1975. Rose, D. H., Henry R. Kraybill, and R. C. Rose. Effect of salts upon oxidase 

 activity of apple bark. Bot. Gaz. 69: 218-236. 5 fig. 1020.— One-tenth normal solutions of 

 all the chlorides tested (potassium, sodium, lithium, caesium, ammonium, calcium, manganese, 

 ferric) decreased oxidation of pyrogallol by apple bark powder. Oxidation v,-as increased 

 very slightly by 0.1 N solutions of all the sulphates tested. Potassium, sodium, and mag- 



