DISEASES OF PLANTS. 453 



distributed, but, except during wet seasons, causes very little injury. Pecan 

 anthracnose, due to Glomerrlla cingulata. Is extensfvely distributed, but has not 

 proved a very serious pest in any locality. Kernel spot, due to Coniothyrium 

 caryogcnum n. sp.. Is said to be rare, and the investigations on this disease thus 

 far have been confined to laboratory and greenhouse work. A technical descrip- 

 tion of the fungus is given. Crown gall, caused by Bacterium tumefaciens, is 

 reported as having been found on pecans in northern Florida and southern 

 Mississippi. 



Observations on rust of mallows, L. Blaringhem (BwZ. Soc. Bot. France, 

 59 {1912), No. 8, pp. 765-773; ahs. in Mycol. Centbl., S (191S), No. S, p. 125).— 

 The author concludes from his observations that the development of Puccinia 

 malvaccarum on Althcca rosea and on A. officinalis is favored by dryness and 

 light, the latter species being the more sensitive to the action of the parasite. 



The influence exerted by rusts on respiration and chlorophyll assimilation 

 by leaves, G. Nicolas {Rev. Q6n. Bot., 25 {1913), No. 297, pp. 385-395).— A 

 comparison of assimilation and respiration in rusted and in rust free leaves 

 of olive, ash, and several other trees is held to show that rusts hinder both these 

 processes. 



A twig blight of Quercus prinus and related species, Della E. Ingram 

 (17. 8. Dept. Agr., Jour. Agr. Research, 1 {1914), No. //, pp. 339-SJf6, pi. 1, figs. 

 7). — The author describes a disease of the chestnnt oak {Q. prinus) which, 

 while primarily a disease of this species, is said to be occasionally found on the 

 American chestnut and the white oak. 



The fungus causing the disease is referred to Diplodia longispora. It is said 

 that large trees are not killed outright, but that they may eventually die as a 

 result of the weakened condition caused by losing the young branches. The 

 saplings are often killed outright. 



Infection takes place through wounds in the bark, and the fungus kas not 

 been found present in leaf tissues. 



A preliminary account of this disease, where it is attributed to Dothiorella 

 quercina, has been noted elsewhere (E. S. R., 27, p. 654). 



Withertip of fir, T. Lagerberg {Skogsvdrdsfor. TidsJcr., Fackafd., 1915, No. 

 S, pp. 173-208, figs. 19; als. in Ri/v. Patol. Veg., 6 {1913), No. 7, pp. 213, 214).— 

 A withertip fungus on fir, causing extensive loss in Sweden, has been studied 

 with the result that the organism is declared to be a form of that known as 

 Brunchorstia destruens, the name Crumenula aiietina n. sp. being applied by 

 the author. 



An undescribed species of Gymnosporangium from Japan, W. H. IjONG 

 {U. B. Dept. Agr., Jour. Agr. ReseoA'cli, 1 {1914), ^o. 4, pp. 353-356).— In a 

 previous publication by Clinton (E. S. R., 29, p. 547) attention was called to the 

 introduction of G. japonicum on Junvperns chincnsis. A study of some of the 

 material has led the author to the conclusion that the rust on the woody stems 

 is this species, but that occurring on the leaves or young twigs differs materially, 

 and this is described as G. chinensis n. sp. 



A leaf disease of Para rubber, C. K. Bancroft {Jour. Bd. Agr. Brit. Guiana, 

 7 {1913), No. 1, pp. 37, 38). — A new but as yet not very abundant fungus is 

 reported as parasitic on leaves of Hevea on a farm in British Guiana. Spots 

 form, increase in size, and finally die and drop out, leaving a hole in the leaf. 

 The fungus was declared at the Kew gardens to be new and was named by 

 Massee PassaJora hevew. A trial of lime-sulphur mixture is recommended, also 

 the destruction of affected leaves before transplanting. 



