No. 2, Decembek, 1921] PHYSIOLOGY 121 



of carbon dioxide evolved does not necessarily correlate either with the amount of dry matter 

 formed or with the amount of glucose reduced. The 3 slow-growing fungi produced more than 

 1 gm. of carbon dioxide for each gm. of glucose. For the remaining organisms the ratio was 

 less than unity, while the dry weight of material produced for each gm. of glucose consumed 

 was in all cases less than unity. The coefficient of respiration varies from 0.8-3 to 2.01, the 

 economic coefficient from 3.86 to 22.86. The amount of carbon dioxide produced is not the 

 amount theoretically possible from the sugar consumed. Alcohols and acids are possible 

 products, and alcohol production is definitely established for Fusarium acuminatum, Rhizopus 

 Tritici, and Diplodia tubericola. — D. Reddick. 



GROWTH, DEVELOPMENT, REPRODUCTION 



767. Andre, Hans. Uber die teleologische und kausale Deutung der Jahresringbildung 

 des Stammes. [On the teleological and causal meaning of annual ring formation in stems.] 

 Naturwissenschaften 8: 99S-100G, 1021-1027. 1920.— This is a brief discussion largely on the 

 basis of general observations and of earlier, published, experimental work. In the treatment 

 of causal relations the author considers the factors to be (a) physical, such as the changing 

 pressure of the cortex; (b) physico-chemical, illustrated by the influence of mineral substances 

 and organic nutrients in determining the sizes of the vessels; and (c) "stimuli," notably 

 such formative stimuli as water and the variable pull and pressure on the cells of the cam- 

 bium. — Or ton Li Clark. 



768. Bowling, John J. Observations of plant growth with the recording ultramicrometer. 

 Nature 107: .523. 1 fig. 1921. — This is a description of the apparatus which has shown "pul- 

 sations of growth" as described by Bose.>— O. A. Stevens. 



769. Ereky, K. Die Steigerungsmoglichkeiten der landwirtschaftlichen Lebensmittel- 

 produktion. [The possibility of increasing the production of agricultural foods.] Naturwissen- 

 schaften 8: 1033-1038. 1920. — The relative efficiency of the different crops grown under the 

 same conditions is shown by a comparison of the number of calories which the products rep- 

 resent. Sugar beets are 1st with a production of 22.3 million calories per hectare, followed by 

 potatoes, 9.5, barley, 6.8, oats, 6.2, wheat, 5.4, and rye, 4.9. This account is designed to convey 

 general information concerning the capacit}' of the plant to utilize light and CO2 in the pro- 

 duction of agricultural foods. Other aspects of food production are discussed. — Orton L. 

 Clark. 



770. Fitting, Hans. Das Verbliihen der Bliiten. [The withering of flowers.] Natur- 

 wissenschaften 9: 1-9. Fig. 1-11. 1921. — The mechanics of leaf fall brought about by an 

 abscission laj'er applies also to the fall of many flowers. There are several distinctive types. 

 There is, however, a significant reaction concerned which is considered a true stimulation 

 process and termed "chorism." Important is the effect of fertilization, which is elaborated by 

 many striking examples. The function of hormones from the pollen and pollen tubes is treated 

 in some detail. Often the same process (fertilization) will prolong the life of flowers of one 

 species (Listera ovata) while it shortens the life of those of other genera and species. — Orton 

 L. Clark. 



771. Levy, Fritz. Neuere Untersuchungen auf dem Gebiete der Zellteilungs-Physiologie. 

 [Recent experiments in the field of the physiology of cell division.] Naturwissenschaften 9: 

 10.5-110. 1921. — The author considers in a general way the influence of growth factors and of 

 division factors in the physiology of cell division. — Orton L. Clark. 



772. AIacDougal, D. T. Growth in trees. Proc. Amer. Phil. Soc. 60: 7-14. PI. 1. 

 1921. — This paper, read before the American Philosophical Society, was presented as a synopsis 

 of a more extensive manuscript to be published by the Carnegie Institution. Two new in- 

 struments, the dendrograph and dendrometer, designed for obtaining measurements of grow- 

 ing trees, are described and illustrated. Measurements made in 1919 and 1920 of a number of 

 evergreen and deciduous trees in various habitats are listed and generalizations summarized. — 

 Wanda Weniger. 



