DISEASES OF PLANTS. 645 



partment relative to the streniitli of wood niul wliicli li:ive been noted from time 

 to time. 



Consumption of firewood in the United States, A. II. Pikuson (U. »s'. Drpt. 

 Agr., Forest Scrr. Circ. ISI. iip. 7, }i<j. I). — Tabular estimates are given and 

 discussed showing the estimated (.•onsumption of firewood by various classes 

 of consumers and the estimated quantity and value by States in 1908 of the 

 firewood used on the farms, in large and small cities, towns, and in mineral 

 operations. These estimates are based upon inquiries sent to more than 48,000 

 county and crop correspondents of the Bureau of Statistics of tliis Department, 

 reports by special agents of the Census Bureau in the larger cities, and informa- 

 tion furnished by mining operators. 



The total quantity consumed is given as 86,000,000 cords with an average 

 value of $2.91 per cord. A little more than 20.000.000.000 cu. ft. of wood in all 

 forms is used in the United States each year, of which 7.000,000,0(X) cu. ft. is 

 firewood. About SI per cent of the firewood is cousumed"ou farms. 



DISEASES OF PLANTS. 



The diseases of cultivated plants and their treatment, H. Faes (Les Mala- 

 dies lies Plantes Cultirees et leur Traitcment. Paris and Lausanne, 1909, pp. 

 256, figs. I'fl). — In this work accounts are given of the principal injuries to 

 which cultivated plants are subject. The order of treatment is as follows: 

 Troubles due to physiological causes, insect pests, fungus diseases, and the 

 attack of phanerogamic parasites, the host plants being grouped into vineyard, 

 orchard, garden, and field crops, and forest trees. The general plan of the 

 work is to describe the pests in terms that are readily comprehended by agri- 

 culturists, while at the same time sufficient detail and scientific accuracy is 

 given to make the book a guide for students in vegetable pathology. It is 

 publishetl under the auspices of the Association of Professors of the Agricultural 

 Schools of Switzerland. 



Symptoms of diseases in plants, F. D. He.\ld (liiil. Unir. Texas, .SVi. Ser. 

 No. J-'f, pp. 63, figs. 62). — The main part of this paper deals with the symptoms 

 of plant diseases produced by fungi and bacteria, brief mention being made of 

 several parasitic phanerogams. 



The principal symptoms of diseases in plants are given as discolorations of 

 tissues, leaf perforations, wilting, necrosis, atrophy, hypertrophy, mummifica- 

 tion, change of posilion, destruction of organs, excrescences, malformation, 

 exudations, and rotting. In addition to a general discussion of the symptoms 

 of diseases common to orchard, field, and garden crops, the author illustrates 

 by photographs the gross appearances of a largo number of these diseases. 



Bacteria in their relation to plant pathology, M. C. Potter (Brit. Mycol. 

 Hoc. Trans., 3 {1909), pt. 3, pp. 150-168, pi. i).— In a presidential address before 

 the British Mycological Society, the author gives a review of a number of i)lant 

 diseases which are attributed to bacteria, concluding the adflress with a bibliog- 

 raphy of the literature relating to bacterial diseases of plants. 



The influence of parasitic fungi on the development of the host plant, 

 DiTTKicii (Jahresher. Schles. (le.sell. Vaterliind. Cult., 1909, II, p. 32; ahs. in 

 Centhl. Bald, [etc.], 2. Aht., 26 (1910), A'o. S-9, p. 2S3).—\t is stated that a 

 parasitic fungus rarely kills the iiost outright. TTsually it either causes no ap- 

 parent alteration of tissues, <n\ if changes are produced, they consist in an 

 atrophied or hypertrojihied condition of tlie diseased portions which later may 

 or may not die according to the character of the parasite. 



