328 BOTANICAL GAZETTE [october 



in connection with biological work, Paul Weatherwax; Bacteria in frozen 

 soil, H. A. Xoyes; Some abnormalities in plant structure, M. S. Markle; 

 Plants of Boone County, Kentucky, James C. -Nelson; Plants new to Indiana. 

 VIII, Charles C. Deam; Analyses of ioo soils in Allen County, Indiana, R. H, 

 Carr and V. R. Phares; The relation of nitrogen, phosphorus, and organic 

 matter to corn yield in Elkhart County, Indiana, R. H. Carr and Leroy 

 Hoffman; Soil survey of Cass County, Indiana, Colonzo C. Beals; Ascomy- 

 cetes new to the flora of Indiana, Bruce Fink and Sylvia C. Fuson; The 

 dormant period of timothy seed after harvesting, M. L. Fisher. — J. M. C. 



Douglas firs. — Henry 25 and Flood have described three American and 

 four Asiatic species of Pseudotsuga, separating the Pacific Coast trees from 

 those found in the Rocky Mountains. Aside from some minor differences in 

 leaf and cone structure, the authors believe that the Rocky Mountain form, 

 P. glauca, shows more xerophytic structures and is much more resistant to 

 injury by frost and drought. The differences in the behavior of the two forms 

 under silvicultural conditions in Great Britain seems to afford a much better 

 basis for considering the eastern form a separate species. Of the Asiatic 

 species, one is native to Japan, one to Formosa, and two are native to Yunnan, 

 China. All are found in restricted areas and are to be regarded as so rare 

 as to be of little economic importance. — Geo. D. Fuller. 



Evaporation and vapor pressure deficit. — It has been shown by John- 

 ston 26 that it is possible, by using vapor pressure deficit and wind velocity 

 data, the former being derived from hygrometer and thermometer readings, 

 to calculate the "potential evaporation" or evaporating power of the air in a 

 manner that will show a very close agreement with the records from the 

 porous cup atmometer. In this way considerable data collected by the 

 Weather Bureau may be translated into terms that are significant and valuable 

 for the ecologist. — Geo. D. Fuller. 



Plantago in Hawaii. — Rock 27 has monographed the two endemic species 

 of Plantago occurring in the Hawaiian Islands. One of them, P. prince ps, is 

 a branching shrub, and its variability is indicated by the fact that 8 varieties 

 are recognized. The other species, P. pachyphylla, includes 7 varieties, among 

 which there is a new one (var. anomala) which combines the characteristic 

 capsule and venation of P. pachyphylla with the seeds and arborescent branch- 

 ing habit of P. princeps. — J. M. C. 



2 s Henry, A., and Flood, Margaret G., The Douglas firs: a botanical and 

 silvicultural description of the various species of Pseudotsuga. Proc. Roy. Irish 

 Acad. 35: sect. B. 67-92. pis. 12-14. 1920. 



26 Johnston, E. S., Evaporation compared with vapor pressure deficit and wind 

 velocity. Mo. Weather Rev. 47:30-33. Jigs. 2. 1919. 



2 7Rock, J.F., The genus Plantago in Hawaii. Amer. Jour. Bot. 7-i95~ 2I °- 

 pi. 13. 1920. 



