1919] DISEASES OF PLANTS. 47 



mangrove forests of British India, with special reference to the utilization of 

 mangrove harks for the preparation of tan extracts. 



The germination and juvenile forms of some oaks, L. 11. I'ammki. and 

 C. M. King (Proc. Iowa Acad. Sci., 24 (1917), pp. 367-391, figs. 66).— This com- 

 prises preliminary notes on germination studies of a number of Iowa species 

 of oak. 



Hybrids of the live oak and overcup oak, H. NESS (Jour. Heredity, 9 (1918), 

 No. 6, pp. 263-268, figs. 3). — The author briefly describes and gives Illustrations 

 of some young hybrid oak trees growing on the Texas Experiment Station 

 grounds that were produced by using the overcup oak (Quercus lyrata) as 

 father and the live oak (Q. virginiana) as mother. 



Note on the dying back of sal seedlings, E. A. Smythies {Indian Forester, 

 44 (191S), No. 9, pp. 420-422, pi. 1). — The results of a preliminary experiment 

 here reported indicate that the rather severe dying back of seedlings of sal 

 (Shorea robusta), due to heavy clearing operations, is not a detriment to the 

 seedlings as large numbers of them throw up new shoots and appear better able 

 to withstand hot weather than seedlings continually growing under shade. 



DISEASES OF PLANTS. 



Fungi and disease in plants, E. J. Butler (Calcutta: Thacker, Spink & Co., 

 1918, pp. VI +547. pis. 5, figs. 201). — This book is presented as an introduction 

 to the diseases of field and plantation crops, especially those of India and the 

 Bast About 200 diseases of crops are included, nearly all of which have been 

 studied by the author in the laboratory and in the field. Fruit and forest tree 

 diseases are not treated, and vegetable diseases are only incidentally mentioned. 



After chapters dealing with fungi as a cause of plant diseases, the author 

 describes the principles upon which control measures are based and gives 

 chapters on special diseases, the arrangement being according to the host plants. 

 Where definite means of control are known, they are given under the different 

 diseases. The book is designed primarily for planters and those interested in 

 the crops, and all the more technical matter is printed in smaller type than the 

 body of the work, so that this information will be available for use by students 

 and investigators. 



An extensive bibliography of plant disease literature is given. 



Report of the plant pathologist, H. E. Thomas (Porto Rico Sta. Rpt. 1917, 

 pp. 28-30). — A brief report is given on diseases observed on vegetables, vanilla, 

 aiKl citrus trees. 



A wilt disease of beans caused by an undetermined Phycomycete, a rust of 

 Lima beans caused by Uredo concors, and a powderly mildew of kidney beans 

 are said to have been abundant during the past season. Tomatoes are reported 

 to have been badly infected with Phytophthora infeatans, and cabbage with 

 the black rot caused by an organism resembling Pscudomonas campestris. 



Among the parasites attacking vanilla, the common leaf spotting alga (31 y- 

 cvidea parasitica), Olwosporium rufomaculans, and a species of Fusarium on the 

 roots were observed. 



Some attention has been paid to the withertip fungus (Collctotrichum glo?- 

 osporioides) of citrus trees, and also to citrus scab (Cladosporium citri). 



[Plant] diseases, J. S. Dash (Rpt. Dept. Agr. Barbados, 1916-17, pp. 59, 

 60). — During 1916-17, the most troublesome disease of sugar cane, particularly 

 young ratoon canes, was ilarasmius sacchari. Collctotrichum falcatum oc- 

 curred in a few places. Thielaviopsis paradoxa continues to be a troublesome 

 disease of cane cuttings. Cercospora vagina- was fairly common. Cephalo- 



