260 • EXPERIMENT STATION RECORD. 



( Wallrothirlld arrrutltohii.) was found parasitic in the fruit of the mistletoe, and it is 

 thought tha;t tlie fungus will to a considerable extent check the spread of the pest. 



Fungus diseases of forest trees, H. von Schrenk ( U. S. Dept. Agr. Yearbook 

 1900, pp. 190-210, p)h. .5). — The author describes some of the more important fungus 

 diseases to which forest trees are subject, giving special reference to such as render 

 the wood unfit for luml^er. The general nature of wood-destroying fungi is described 

 and the method by which trees become infected indicated. Among the more 

 destructive fungi the autlior describes Tranietcs plni, Polyporus sdni'einitzn, P. sul- 

 fureus, P. igniarius, P. 'nigricans, P. annosics, P. rimosns, and P. junipt'rlnus. In 

 order to save the timber it is recommended that as soon as dead or severely attacked, 

 diseased timber should be cut. This will prevent depreciation in the value of timber 

 and also the scattering of the spores to other trees, thus spreading the disease. 



A disease of elm trees, B. G. AliSo {Jour. Roy. Hort. Soc. [London'], 33 {1900), 

 No. 3, p)p- 343-345). — A disease affecting elm trees near Tarancon, Spain, is described. 

 The trees at this place are largely cultivated for timl)er, but have recently been trou- 

 bled with a disease which while not apparent on the living trees, shows itself very 

 plainly in the timber. The trees appear healthy and there is no external sign of 

 deterioration, nor of any fungi or insects. They seem to be in a normal condition, 

 the foliage being abundant and fruit fully up to the normal. They continue in this 

 condition mitil full grown, when cracks appear in the trunk, generally on the surface 

 at first but increasing in depth with the age of the tree until in old specimens the 

 cracks pierce to the heart of the tree. It often happens that no injury is present 

 when a tree is cut, but the wood after being worked falls to pieces. The author has 

 made a careful study of the subject, but has been imable to determine definitely the 

 cause of this peculiar behavior of the trees. As no parasites are present it is believed 

 to be a disturbance of the physiological functions of the tree. 



Concerning- some fungi occurring on tropical culture plants, A. Zimmermann 

 ■{Ccntbl. Baki. u. Par., 2. AU., 7 {1901), Nos. 3,2ip. 101-106; 4, pp. 139-147, Jigs. 24).— 

 Critical notes are given and new species described of a number of fungi which have 

 been observed on economic plants in various parts of Java. The host plants in most 

 cases were tea, coffee, cacao, betel, and Melia azedarach. 



Two ne-w smuts on Eriocaulon septangulare, G. P. Clinton {Rhodora, 3 

 {1901), No. 28, pp. 79-82, Jigs. 2). — Descrijitions are given of 2 new species of smuts, 

 namely, T(ih/}>osp)orin))i erioaadl and Ustilago eriocauU. 



A new disease of Caragana arborescens, A. von Jaczewski {Ztschr. Pflanzen- 

 krank., 10 {1900), No. 6, p/>. 340-343). — A description is given of a fungus disease of 

 Caragana, which is due to attacks of an undescriljed species, to which the name 

 Pleospora caraganx is given. This was previously noted from a Russian publication 

 (E. S.R., 12, p. 859). 



Chlorosis, a physiological study, ('. CnEVALiEii {Bdg. Jfort.et Agr., 12 {1900), 

 No. 9, pp. 132, 133). 



Description of the infection house and system of experiments of the 

 Dahlem experimental field, C. von Tubeuf {Arb. K. Gesundheitsamte, Biol. Abt., 

 2 {1901), No. 1, pp. 101-103, figs. 4). 



ENTOMOLOGY. 



Report of the entomologist, J. Fletcher ( Canada Expt. Farms Rpts. 1900, pp. 

 195-248, figs. 18). — Hessian fly was unusually destructtve during the season. In 

 some stems of infested wheat, this insect was found associated with the wheat stem 

 maggot. The Hessian fiy was active and laid eggs considerably later in the fall than 

 is usually the case, thus necessitating a delay in the fall wheat sowing for a week or 

 more. The wheat stem sawfly {Cephus pygmseus) is reported as injurious in the 

 Northwest Territory. For combating this insect the author recommends burning or 



