272 BOTANICAL GAZETTE. [ October, 



(Phytophthora) with four applications of half strength solution; H. W. 

 Wiley gave analyses of sorghum seed and spoke of its comparative food 

 value, and also of the nature of the red coloring matter of the seed and 

 glumes. Two papers by B. D. Halsted, " The cranberry gall fungus " and 

 " Our worst weeds," were read by title only. 



It has proved a difficult task to settle experimentally the place of 

 the transpiration stream in plants, particularly in the herbaceous dicots 

 and the monocots. Long ago the experiment of " ringing " the trunk of 

 the woody plants determined that it was either in the wood body or pith 

 that the water was conducted, and reasoning showed pretty conclusively 

 that the pith could not have anything to do with this work. But recently 

 Hartig and Wieler have differed widely as to what parts of the wood were 

 most active in conduction. A long step forward in the experimental 

 work on this function has been made by Bokorny 1 in hitting upon the use 

 of iron sulphate. For a long time various liquids have been used in the 

 endeavor to ascertain the rate of the transpiration stream ; at first color- 

 ing matters in solution, and later salts of lithium. The difficulty with the 

 latter is that while they can be easily detected spectroscopically in any 

 region of the plant, it is not practicable to detect them in a tissue nor to 

 discern whether they are in the walls or the lumen. Iron sulphate pos- 

 sesses the three necessary qualities of not being seized upon by any par- 

 ticular part of the plant, of not injuring the cells and of being easily rec- 

 ognized in loco by a simple microchemical reaction. It is used in .the 

 proportion of 1:500 or 1:1000 of distilled water, and its presence in any 

 tissue can be detected by the use of a watery solution of ferricyanide of 

 potassium (1:10). In general, Bokorny's results agree with the statements 

 of Sachs (Cf. Vorlesungen tiber Pfl.-Phys.) except in the important par- 

 ticular that often tissues that are not lignified (e. g., epidermis, collen- 

 chyma,soft bast) are water-conducting, so that Sachs' insistence upon the 

 hgnification of the walls as the reason of their permeability falls to the 

 ground. Whether in woody plants or herbs, it is the vascular bundle 

 chiefly in which the water travels, though in some collenchyma and 

 sclerenchyma are also conducting. In the vascular bundles it is chiefly 

 the xylem which carries the water, sometimes the thin-walled bast. In 

 all cases the water goes in the wall, and not in the lumen of the cell. 



Leo Lesquereux, our most eminent bryologist and palseo-botanist, 



died at his home in Columbus, Ohio, on Friday, October 25th, aged almost 



eighty-nine years. Some years ago failing sight compelled him to give 



up his bryological studies, and his strength has been gradually failing. 



We hope to give a further account of his life and works in our next 

 number. 



^iologisches Centralblatt, ix, 1889, p. 289 ; Ueber den Ort der Wasserleitung in den 



Pflanzen. 



