mSKASKS OK PLANTS. 63 



"In the foregoing, two forms of di'cay have been (lencribed, one destroying wood 

 of Td.rodkaii (lifftichmii, thi' other of LihoceilniN (lernrrernf. In both case.s the wood iss 

 destroyed in loeaHzed areas, whieh are snrrounded l)y apparently sonnd wood. The 

 cell walls are ehanujed into coinpoinids whieh diffnse through the walls and till the 

 cells surrounding the decayed center; an<l these have been called humus compounds. 

 In both, a fungus mycelium occurs with strongly marked characteristics, which 

 nourishes within the diseased centers and grows between these centers without affect- 

 ing the intervening wood. This wood can be utilized for many purposes even when 

 much rotted, and in neither case does the mycelium grow after the tree has once 

 been cut down. . . . The two forms of decay differ but slightly, and not more than 

 might be expected in two woods of different character. Taking these facts into con- 

 sideration, it appears probable that the two diseases are caused by one and the same 

 fungus, the fruiting form of which has not yet been found." 



A new species of Trimmatostroma, M. W. Doherty {Bot. Gaz., 30 {1900), No. 

 6, pji. 400-4('->, fj(/s. .)') . — Jn the sununer of 1898, the author's attention was called to 

 a diseased condition of the balsam tirs in the province of Ontario, Canada. The 

 disease at this time had done but little damage and all efforts to collect fruiting 

 material of the fungus was futile. In 1899, the author visited the same locality and 

 found that trees which the previous season showed only an occasional dead branch 

 had entirely succumbed and the disease was spreading rapidly, many new points of 

 infection )>eing noticed. At this time the diseased leaves showed the presence of 

 numerous l)lack warty tubercles, which jjroved to be fruiting masses of the fungus. 

 A quantity of material was collected and subjected to further examination and study. 

 From observations made on cultures, the author has decided the fungus is new and 

 has given it the name Trlmmutostrom<t. abkl'ma. The technical characters of the 

 fungus are described, from which it appears that it belongs to the section Phragmos- 

 porae of the Hyphomycetes. Thus far the only hosts on which the fungus has been 

 observed are Abies alba and .1. balsamea, but it is thought probable the spruces are 

 not immune. 



The rust of white pine, C. von Tubeuf {A(/r<)ii(»iit', lUOO, pp. 377, 378). 



Concerning- a fungus disease of the Norw^ay spruce, R. Beck ( Tliarand. 

 Forst. .hihrb., 50 {1900), })p. 178-194, pi. 1) . 



On the use of a copper-soda mixture for the prevention of pine-leaf cast, 

 F. (Jrundner (.1%. For^t ii. Jugd Ztg., 1900, Nov., pp. 369-37i2). 



Studies on the hexenbesens of barberry, J. Eriksson (Landl. Akad. Handl. 

 Tidskr., 39 {1900), No. 5-6, pp. 346-360, pis. ^).— The results are given of inocula- 

 tion experiments with .Ecldhim gravenJnia and Piirclnia arrhenatberi. 



Wakker's hyacinth germ (Pseudomonas hyacinthi) , E. F. Smith {U. S. 

 Dept. Agr., Division of Vegetable Fligsiology and Fatliology Bid. S!6, pp. 45, pi- 1, 

 Jigs. 6). — In this 1)ulletin the author gives an account of the morphology of the organ- 

 ism which causes the rotting of hyacinths known as "Wakker's disease." The 

 organism was isolated, and several .series of inoculation experiments begun in 1897 

 and carried through 1899 are described in detail. In these inoculation experiments 

 hyacinths, onions, cabbages, and other plants were experimented with. The patho- 

 genic nature of the organism is clearly established through the inoculation experi- 

 ments, as the symptoms always began in that part of the plant which had been 

 inoculated and proceeded downward, the V)ulb being the last part to show the dis- 

 ease, and because the organism was found present in the yellow bundles of the bulbs. 

 The morphology of the organism is described at considerable length and a synopsis 

 of its characters given. The organism is said to be closely related to the ones caus- 

 ing the bacterial brown rot of cruciferous plants and the bacterial disease of l)eans, 

 and somewhat less so to that causing the bacteriosis of sweet corn. It is readily dis- 

 tinguishe<l from the first two by its brighter color, lower thermal death point, and 

 manner of growtii. It is distinguished from the organism causing the bacteriosis of 



