DISEASES OF PLANTS. 



647 



Notes are given on the number of seeds produced by some weeds, 

 the author having determined approximately the number of seeds pro- 

 duced by a single plant of some of the more common weeds. The fol- 

 lowing table shows the approximate number of seed produced by some 

 of the worst weeds : 



Number of weed seed produced by a single plant. 



The authors have made some investigations relative to the fertili- 

 zation of flowers and have found that the following are dependent 

 on insect visits: Portulaca oleracea, Ipomcea hederacea, I. purpurea, 

 Solatium rostratum, and Euphorbia maculata. The following species are 

 self fertile: Abutilon avicennm, Hibiscus trionum, Iva ciliata, Bidens 

 frondosa, Amarantus retrojiexus, Acnida tuberculata, Ghenopodium album, 

 Phytolacca deeandra, Polygonum pennsylvanicum (seed smaller than 

 average), Euphorbia marginata, Panicum sanguitiale, Setaria glauca, and 

 Eragrostis major. 



The authors discuss the subject of the eradication of weeds and 

 give a list with descriptive notes of 209 species. 



Massachusetts weeds, G. E. Stone (Agr. Massachusetts, 1897, pp. 268-277). — A 

 popular article on the dissemination, distribution, aud eradication of weeds. 



A new wild lettuce from New England, B. L. Robinson (Bhodora, 1 (1899), No. 

 1, pp. 12,13, pi. 1). — The author describes Lactuca morssii from Massachusetts. It 

 somewhat resembles L. canadensis and L. leucophwa. 



Matricaria discoidea in eastern Massachusetts, W. H. Manning (Iihodora, 1 

 (1899), No. l,p. 18). — Tbe occurrence of this weed at several stations is noted and it 

 is said to be apparently driving out tbe common mayweed, Anthemit cotula. 



On the destruction of orobanche on clover, A. Lonay (Jour. Soc. Agr. Brabant- 

 Hainaut, 1898, No. 38). 



DISEASES OF PLANTS. 



Report of the botanist, G. E. Stone and R. E. Smith (Massachusetts 

 Hatch Sta. Bpt. 1897, pp. 47-70, pis. 2). — The authors give a brief review 

 of the work conducted during the past year and report more at length 

 upon some of the particular lines of investigation. 



The causes of the failure of the potato crop of 1897 were investigated. 

 Among otber causes may be mentioned the extremely wet condition of 

 the soil at planting time, which is thought to have induced the rotting 

 of the stems of the young plants just below the ground. The authors 



