177 BOTANICAL GAZETTE. 



II. The second paper considers the two theories to explain the 

 tendency of cuttings to produce roots near the Aw(?/ end,* and buds 

 near the <^//W^/ end. Vocliting ("Organbildung im Pflanzenreich," 

 Bonn, 1878) beheves this tendency to be innate, and growth-in- 

 herited. Sachs, in a hite paper (Arbeiten des bot Inst. W'urzburg, 

 1880, p. 452) opposes the theory of Vocliting in Mo and conceives 

 that Vochting's mori)hr)logica' force is reaUy a tendency impressed 

 upon the forming cells by the action of external agencies, especially 

 that of gravity. 



Darwin observed carefully the rooting of the species of the sterile 

 shoots (if brambles growing on steep banks. In such positions the 

 majority of the branches grow immediately downward or strag[;le out 

 horiznntally and then turn downward. But some grow uphill, yet he 

 finds the tips of many of these branches, indifferent as to position, 

 taking root. The gravitation impulse therefore seems not to be ap- 

 plicable to such a case. Mr. Darwin then proceeds t < show that it is 

 better for the plant thit the morjjhological growth-impulse should 

 determine the formntion of roots at the tip than that root formation 

 should depend on the guiding force of gravity. Injury is most likely 

 to occur at the end of the branch. The new shoot that is to be pro- 

 duced to perform the function of the original branch will have the 

 best chance of success if it starts from the point reached by that 

 branch before the injury ; therefore the growth ot the bud nearest the 

 apex is the most advantageous for the plant. 



It must be remarked that some of the conclusions drawn, if Mr. 

 Darwin is correctly reported by Nature, do not seem warranted by 

 the result of the experiments, but it would be hardly just to criticise a 

 paper from a mere abstract.- C. R. B. 



Peronospora vilicola, DeBary. —American grape vines having 

 been introduced into Europe, with the expectation that they would 

 better withstand the attacks of Phylloxera, have carried this parasite 

 with them, and within two years it has spread over all the vine growing 

 countries. 



It was first found in Hungary in 1877 ; in 1878 in South-western 

 France ; in 1879 it occurred in a number of provinces, and in 1880, 

 everywhere, doing immense damage. In 1879 it was discovered in 

 Italy and Switzerland, and in 18S0 in T)to1, Steyermark and Lower 

 Austria. Mde Hedwigia.— Y. W. Holwav. 



A New Grass. — While on a botanical trip with my friend H. N. 

 Mertz around Lake Chautauqua, N. Y., last summer, we found on a 

 road at Fairpoint upon the "Association grounds" a grass which puz- 

 zled us considerably. It was an annual with tufted, linear root leaves 

 45 inches long; slender, leafy culm 15-18 inches high, ending in a nar- 

 row spike about two inches long, consisting of numerous 5-6 flowered 

 spikelets each enclosed nnthin two ovate pinnaicly-divided braets [gluiues'l). 



*That end originally uciiropt the body of tho p:ironf phint. 



