DISEASES OF PLANTS. 767 



The fungi causiiig the 2 diseases above described are believed to be 

 wound parasites which gTOW in the heartwood of living trees, render- 

 ing the wood unlit for commercial purposes. Frequentlj^ diseased 

 trees are cut and sold us an inferior grade of fence posts, although 

 apparently they last almost as long as sound ones. The natural supph'' 

 of red cedar still availal^le is verv small and any remedies which might 

 be suggested in connection with these 2 diseases must be applicable to 

 trees growing under modern methods of forestry for lumber or orna- 

 ment. After a tree has once become affected, remedies will not avail. 



The more important fungus diseases of agricultural plants and means for 

 their prevention, E. Hotter (Die widitigsten Pilzkrankheiten der landwirthKchaftUchen 

 K'ulturyewdclise and iJire Bekampfung. Graz: Leuschner & Lubensky, 1900, pp. 60, 

 figs. 47). 



Some parasitic fungi of cultivated plants, G. Bkiosi and F. Cavara {Ifunghi 

 parassiti. deUe jhhiiIc coJtivati' od nlill essicrati, delineati e descritti, Fasc. XIII, XIY. 

 Pavia, 1900; abs. in Bot. Centbl, 84 (.1900), Xo. 1, ]3p. 14, 15). — In a list of 50 species 

 of parasitic fungi, the authors have described the following new species: Ovularia 

 medicagunk, parasitic on alfalfa leaves; Melogramma henriquetii, on branches of cork 

 oak; Eamularia vallisumhrosx, on narcissus leaves; Cercospora ariminensis, on sulla 

 leaves; C. heHanthemi, on helianthemum; C.hypophyUa, on Posa canina; C.ticinensis, 

 on leaves of Scanbucus nigra; Ascochyta polemonii, on polemonium; and Lepothyrium 

 peronx, on peony leaves. ^ 



Potato and apple scab, G. E. Stone {Massachusetts State Pd. Ayr. Leaflet Xo. 7, 

 jjp. 4, figs. 2). — A popular description is given of the potato scab, caused by Oospora 

 scabies, and the treatment of the seed tubers with corrosive sublimate or formalin 

 solutions recommended. The apple scab, due to Fusicladium dendriticum, is l>riefly 

 described, and as remedies the author recommends 5 sprayings with Bordeaux 

 mixture in which Paris green is added to the second and third for the destruction 

 of the cankerworni, curculio, etc. 



The black knot of the plum and cherry, G. E. Stone {Massachusetts State Pd. 

 Agr. Leaflet Xo. S, j)}). 4, figs. 2). — The black knot of the plum and cherry, caused by 

 the fungus Plowrightia morbosa, is popularly described and remedies suggested. 

 Spraying with Bordeaux mixture and careful attention to orchards, and the removal 

 of all badly infested trees, are recommended. 



The black leaf spot of maples, E. Marchal and J. Huberty {Pal. Sac. Cent. Forst. 

 Belg., 7 {1900), Xo. 1, pp. 1-4, fig. 1). — A description is given of the leaf si:)ot caused 

 by the fungus Rhytisma acerinum. This disease usually makes its appearance in 

 Belgium in the month of July and may prove of considerable injury, especially to 

 nursery stock. 



An experiment in its prevention is brief!}' outlined, in which nitrate of soda at the 

 rate of 250 kg. per hectare was used as a fertilizer with decided advantage. The dis- 

 ease was very abundant in maple plantations surrounding the plats, as well as on the 

 check plat, but the area receiving the nitrate of soda remained absolutely free from 

 the disease. 



A red mold, R. G. Curtis {Proc. Indiana Acad. Sci., 1898, pp. 202-208, pis. 4). — 

 Descriptive notes are given in which the characteristics exhibited during the growth 

 of a red mold are described. 



Notes on Aspergillus oryzse, Katherine E. Golden {Proc. Indiana Acad. Sci., 

 1898, j:>p. 189-201, jils. 5). — Notes are given on the history, morphology, and physio- 

 logical characteristics of this well-known Japanese mold. The author's investiga- 

 tions showed, so far as her experiments went, that there was no indication that 



