632 EXPERIMENT STATION RECORD. [Vol.41 



employing methods somewhat different from those previously used (E. S. R., 

 32, p. 127), the authors claim that where the crop is thoroughly adapted to the 

 region in which it is grown the water requirement approaches its minimum, 

 but is relatively high when the crop is not well adapted. Water requirement 

 is not correlated with any one condition of the environment. Cool weather 

 crops as a rule will have a low water requirement in cool seasons and a high 

 water requirement in warm seasons. In case of warm-w'eather crops the reverse 

 is usually true, although the effect is less marked, a cool season being con- 

 ducive to a low evaporation rate. 



On the osmotic concentration of the tissue fluids of desert Loranthaceae, 

 J. A. Haeeis (J/ew. Torrey Bot. Clitb, 11 (1918), pp. 507-3 J5).— Having con- 

 tinued previous work (E. S. R., 37, p. 47), the author here presents results of 

 studies on sap concentration of the tissue fluids of desert mistletoes and that 

 of their hosts for comparison with those for the rain forest series already noted. 

 The investigation included Phoradendron coryce, P. macrophyllum, and P. 

 californicum on a number of hosts. 



The osmotic pressure of these mistletoes was, roughly speaking, twice as 

 great as was found in the Blue Mountains of Jamaica. In desert Loranthaceae, 

 as in those of the montane rain forest, the osmotic concentration of tissue fluids 

 was generally, but not invariably, higher than that of the host. 



The effect of soaking in water and of aeration on the growth of Zea mays, 

 F. M. Andeews and C. C. Reals {Bui. Torrey Bot. Club, Jf6 (1919), No. 3, pp. 

 91-100, figs. 5). — In this work it was found that 12 hours is the optimum period 

 of soaking seed of Z. mays in order to obtain increa.sed growth, and that growth 

 is retarded temporarily by too long a period of soaking. Puncturing or par- 

 tially removing the seed coats accelerates germination. Aerating the culture 

 solution accelerates growth. 



Comparative studies on respiration. — VI, Increased production of carbon 

 dioxid accompanied by decrease of acidity, M. Iewin (Jour. Gen. Physiol., 1 

 (1919), No. 4, pp. 399-403, figs. 2).— Having noted that high concentrations of 

 ether greatly increased carbon dioxid production by animals, and that this is 

 associated with irreversible changes ending in death, the author, in order to 

 obtain light on the question arising as to whether this increased evolution of 

 carbon dioxid might not indicate increased respiration, experimented with two 

 organisms. Salvia involutyrata and S. splendens, in which death is not accom- 

 panied by increase of acidity. It was found that in petals of Salvia high ether 

 concentrations increased oxygen consumption and carbon dioxid production, a 

 decrease occurring at the same time in the acidity of the cell content. 



On the decomposition of cellulose by an aerobic organism (Spirochseta 

 cytophaga n. sp.), H. B. Hutchinson and J. Clayton (Jour. Agr. Sci. [Eng- 

 land], 9 (1919), No. 2, pp. US-nS, pis. 3, fig. i).— An account is given of the 

 study of an organism found in the llothamsted soils which is able to break 

 down cellulose with comparative ease and which presents features of morpho- 

 logical and physiological interest. The organism, which is said to be more 

 closely allied to the Spirochajtoideie than with the bacteria, is named Spiro- 

 chwta cytophaga. It does not grow in the usual way on nutrient gelatin or on 

 agar. Cellulose is the only carbon compound found to favor its growth. Evi- 

 dence is adduced to show the relation of cellulose decomposition to the assimila- 

 tion of atmospheric nitrogen. 



Influence of temperature and hydrogen ion concentration upon the spore 

 cycle of Bacillus subtilis, A. Itano and J. Neill {.Jour. Gen. Physiol, 1 {1919), 

 No. 4, pp. 421-428, figs. 2). — Data resulting from this investigation are given 

 with discussion. Automatic adjustment of the medium seems to play a role in 



