132 PHYSIOLOGY [Bot. Absts., Vol. V, 



towards the five media used they are remarkably similar, but they show a somewhat striking 

 difference in their powers of growing in the presence of oxygen. — The use of methods, such as 

 those described, for investigations of the biochemical properties of bacteria in general is 

 discussed, and a means is suggested for using these methods with aerobic organisms. — W. W. 

 Bonus. 



937. Hawkins, Lon A., and Rodney B. Haevey. Physiological study of the parasitism 

 of Pythium debaryanum Hesse on the potato tuber. Jour. Agric. Res. 18: 275-297. PL 85-S7. 

 1919.— See Bot. Absts. 4, Entry 1298. 



938. Rosenheim, O. Biochemical changes due to environment. Biochem. Jour. 12: 

 283-289. 1918. — Only one-fourth the amount of chromogenic substance, probably flavone, 

 was produced in the inflorescence of "Edelweiss" in London as in the native Alps. The differ- 

 ence is attributed to biochemical adaptation, possibly placing the flavones in a protective role 

 against ultraviolet light. — W. H. Chambers. 



939. Tevis, May. Symbiotes or benevolent microbes and vitamines. Sci. Amer. Sup- 

 plem. 88: 282-283. 1919. — This paper is in the main a review of the theories and experiments 

 of M. Paul Portier. According to these views, there are no simple organisms except bacteria, 

 all higher organisms being in reality twofold — the organism itself and the microorganisms 

 distributed throughout its tissues. The mitochondria, a definite number of which exist in 

 each cell, are believed to be symbiotes, that is, polymorphic forms of bacteria. The cell 

 apparently limits the number of symbiotes. — It is held that certain wasting diseases, such as 

 scurvy, beri-beri, etc., are not due to the lack of vitamines, but are caused rather by a defici- 

 ency of symbiotes. — Chas. H. Otis. 



GROWTH, DEVELOPMENT, REPRODUCTION 



940. Anonymous. Vertikales Wachstum der Baume. [Rev. of: Cambage, R. H. The 

 vertical growth of trees. Jour, and Proc. Roy. Soc. New South Wales 52 : 377-384. 1919. See 

 Bot. Absts. 5, Entry 943.)] Naturwissenschaften 7: 354. 1919. 



941. Buchanan, R. E. Life phases in a bacterial culture. Jour. Infect. Diseases 23: 

 109-125. 1918. — The growth of a culture of bacteria from initiation until death is divided 

 into 7 phases, and mathematical formulae are presented to express the relation of the growth 

 curve to time for each phase. — W. H. Chambers. 



942. Budington, R. A. Influence of certain ductless gland substances on the growth of 

 plant tissues. Biol. Bull. [Woods Hole] 37: 188-193. Fig. 1. 1919.— The growth of root-tips 

 of Allium is retarded by the presence in their fluid nutrient environment of thyroid gland 

 material, retradation being approximately proportional to the amount of thyroid substance 

 present. The growth of the early leaves is not modified. Iodine, used as KI, in amounts 

 equivalent to that in thyroid substances provoking marked modifications of growth, had no 

 appreciable effect on growing root-tips. Pituitary substances up to two grains of the desic- 

 cated gland, and supra-renal substances up to one grain of the desiccated gland, in 120 cc. of 

 nutritive solution had no effect on the growing root-tips. The experiments, which were lim- 

 ited to a single form, indicate that thyroid constituents may influence the role of protoplasmic 

 action in cells other than those of animal tissues. — J. E. Weaver. 



943. Cambage, R. H. The vertical growth of trees. Jour, and Proc. Roy. Soc. New 

 South Wales 52: 377-384. 1919. — Vertical growth in the trees studied is practically limited to 

 the terminal shoot, and it is very probable that when once definite branches are developed 

 the portion of the axis below these increases in diameter but not in length. — B. M. Duggar. 



944. Hibbard, R. P. The condition of fruitfulness. [Rev. of: Kraus, E. J., and H. R. 

 Kraybill. Vegetation and reproduction with special reference to the tomato. Oregon Agric. 

 Exp. Sta. Bull. 149. 90 p., 22 fig. 1918.] Plant World 22: 23-24. 1919. 



