i88 9 .J 



BOTANICAL GAZETTE. 27 I 



Saposchnikoff finds 4 that sugar can be transformed by the leaves into 



starch. In his experiments he placed plants of various sorts in the dark 



for a time, then cut off some leaves and bisected each along the midrib. 

 One-half was tested for starch, the other was laid for 4-18 days in a 10-20 

 percent, solution of cane sugar, and then tested for starch both with 

 iodine and by Faulenbach's method. Starch was found in abundance, 

 especially along the veins. When the lower end of a leaf of Cordyline 

 rubra was dipped 5 mm. in the sugar the leaf was black under the iodine 

 test as far as 7 mm., from which point up to 10 mm. the color gradually 

 became less deep, but extended far along the veins. In variegated leaves 

 only the chlorophyllous cells formed starch. 



Those who have used the paraffin imbedding method for serial sec- 

 tions (see this journal for January, 1888) have doubtless wished for some 

 simplification of the process of staining. This may be done, according to 

 Dr. Kukenthal, by dissolving the coloring matter in absolute alcohol and 

 dropping the solution into turpentine until the desired depth of color i 

 secured. Sections fixed to the slide with the collodion are kept in the 

 oven until the clove oil has completely evaporated, the paraffin disso ved 

 in turpentine as usual, and the slide brought into the dye. The staining 

 is quickly effected. Overstating may be corrected by placing the slide 

 for a short time in a mixture of acid-free absolute alcohol and turpentine 

 (equal parts ?). Turbidity of the coloring fluid may be corrected by add- 

 ing a drop or two of alcohol. Meyer's carmine, methyl green, methyl- 

 blue?, gentian- violet, safranin, Bismarck-brown, eosin, fuchsin, tropaeohn 

 and malachite-green may be used in the above way. 



The Society for the Promotion of Agricultural Science held its tenth 

 annual meeting at Toronto, August 27 and 28. Twenty-five papers were 

 presented, of which the following are of botanical interest : J. C. Arthur, 

 " What is common wheat rust?" the conclusion being reached that the 

 most abundant and damaging rust of this country is not Puccima gram- 

 inis, as usually assumed, but P. rubigo-vera; W. J. Beal, " A study of 

 bird's-eye maple," specimens of wood from maple and other trees being 

 shown to illustrate various appearances and peculiarities of this mwfor- 

 mation, but no conclusion regarding the cause arrived at, also Wild 

 grasses under cultivation," giving the result of raising the glaucous form 

 of Elymus Virginicus from seed, only two plant* out of four hundred 

 reverting to the non-glaucous form ; C. E. Bessey, " The grass problem in 

 Nebraska," giving an account of the distribution and economic value of 

 the most prominent native grasses, and the su cess attained in introduc- 

 ing the cultivated ones ; T. J. Burrill, "A bacterial disease of Indian corn, 

 describing an important disease chiefly affecting the roots and lower in- 

 ternodes; P. L. Scribner, "Grasses of mountain meadows and deer 

 parks," among which species of Danthonia were considered the most im- 

 portant economically. Several other papers contained more or to 



puiu&iib economically. ocvciai vm^* ™j~-_ Ar;l ;ii„ a 



botanical matter, among which were the following : Man ly Jtoles i illus- 

 trated a paper on soil mttabolism by showing test-tubes sa d to have been 

 etched by soil bacteria grown in nutrient material without pot «h - M- A. 

 Scovell gave an account of experiments with potatoes in which JJijhting 



I the comparative yi 



the experiment ind 



potatoes with Bordea 



Wee< 1 



4 Berichte. d. D. bot. Gesells., vli. 258. 



