540 EXPERIMENT STATIOiST RECORD. 



[Reports from Dutch East Indies on plant diseases], Knischewsky 

 (Ztschr. Pflanzenkranlc, 23 {1913), No. 6, pp. 338-345) .—Bviet notes are given 

 regarding attacks, injuries, and diseases affecting economic plants in the Dutch 

 East Indies, particularly tobacco, coffee, rubber, and cacao, with citations to 

 some articles published reporting inA'estigations thereon. 



Culture experiments with rust fung'i, H. Klebahn {Ztschr. Pflanzenkranlc., 

 24 {19U), No. 1, pp. 1-32, figs. 23).— Reporting work done in 1912 and 1913 in 

 continuance of that previously noted (E. S. R.. 28, p. 242), the author deals in 

 considerable detail with the various factors affecting viability and germination 

 of the teleutospores and the duration of germinability by uredospores, some new 

 hosts of Cronartimn asclepiadeum and of Coleosporium spp., and some studies on 

 Puccinia malvaceartim. 



Experiments with Puccinia spp. show that repeated soaking with fresh water, 

 preferably alternating with fairly complete drying out, is a large factor in de- 

 termining duration of viability in teleutospores. Tbe air content of the water 

 is perhaps also influential in this regard. Winter cold is thought to be neither 

 essential nor influential as regards viability of teleutospores. Uredospores ob- 

 tained early in August and later placed on germinating wheat showed a de- 

 crease of germinability with age, scarcely any germinating when sown after 

 being kept dry for 2^ months. 



Infl.uence of the host on the morphological characters of Puccinia ellisiana 

 and P. andropogonis, W. H. Long ( U. 8. Dept. Agr., Jour. Agr. Research, 

 2 (1914), No. 4, pp. 303-319). — In continuation of a previous note on the possi- 

 bility of P. ellisiana having its fecial stage on Pentstemon and species of Viola 

 (E. S. R., 28, p. 551), the author has continued his investigations and presents 

 the results of cultural data, in which numerous inoculations were made, show- 

 ing that P. ellisiana has two widely separated fecial hosts, Viola and Pent- 

 stemon. 



The infection of Pentstemon is vigorous and abundant and the characters of 

 the fungus are completely changed after passing through Pentstemon assuming 

 in every essential feature those belonging to the Pentstemon rust, P. andro- 

 pogonis. The characters of the rust obtained by inoculating species of Viola 

 with P. andropogonis are identical with those of the regular Viola rust. The 

 transfer of P. ellisiana from Pentstemon back to the Viola is more difficult than 

 from Viola to Pentstemon. It is believed that P. andropogonis may easily have 

 originated in nature from P. ellisiana. 



Witches' broom, E. Lem£e {Jour. Sac. Nat. Hort. France, 4- ser., 15 {1914), 

 Apr., pp. 229-246, figs. 15). — The author illustrates and describes the witches' 

 brooms produced by the various rusts on fir trees and red currants; species of 

 Exoascus on birch, hornbeam, cherry, pear, apple, plum, and elm; those on a 

 number of trees caused by various insects; effect of mistletoe on junipers; and 

 witches' brooms on junipers, spruce, and pin<?, due to causes unknown. 



The parasitism of smut fungi, W. Lang {Jahresher. Ver. Angew. Bat., 10 

 {1912), pp. 172-180). — A brief historical discussion is followed by an accoimt 

 of the author's study of grain plants affected with smut in regard to the locali- 

 zation and mode of invasion and the vegetative life of the parasite within the 

 host. It is stated that while mycelium arising from spores dusted on the 

 stigma develops abundantly between cells which show lessened turgor, neigh- 

 boring tissue retaining high turgidity is generally not invaded. Only in very 

 dry seasons is the mycelium checked in development before leaving the young 

 seed, where it enters the resting stage. The subsequent development of the 

 parasite is described. 



An extension of the studies is contemplated. 



