1019] DISEASES OF PLANTS. 745 



Eucalyptus paniculata, as previously systematically placed, includes four dis- 

 tinct timbers varying in color and other qualities. It is here proposed to take 

 the white, gray, or light chocolate-colored timber as the type E. painculata and 

 to give specific rank to the other three timbers as follovps : Bloodwood-bark iron- 

 bark (E. fergusoni n. sp.), pink ironbark (E. nanglei n. sp.), and narrow-leaved 

 ironbark {E. heyeri n. sp.). 



These species are described and illustrations are given of the fruits and the 

 color and texture of the woods. 



[Bubber investigations on the Gold Coast, 1916 and 1917] (Govt. Gold 

 Coast, Rpt. Ayr. Dcpt., 1916, pp. 3, J,, 6, 7, 8, 15, 16, 20, 25, 26, 21, 29, 30, 31, 

 32-34, 35, 37, 38, 40, 42, /.3, 48, 49, 52, 55, 56; 1917, pp. 3, 5, 6, 7, 12, 23, 24, 25, 

 27, 30, 31, 32-37, 39, 41, 42, 45, 46, 47, 54, 55, 57, 59, 60, 6i ) .—Progress reports on 

 cultural and -tapping experiments with various kinds of rubber at the various 

 agricultural stations and substations in the Government of the Gold Coast. 



On the occurrence of crystals in some Australian timbers, R. T. Bakeb 

 (Jour, and Pmc. Roy. Soc. N. S. Wales, 51 {1917), pp. 435-444, pis. 9).— Out of 

 22 orders of Australian trees examined, calcium oxalate crystals were found to 

 occur in the secondary wood of 15. A descriptive list is given of the species in 

 which crystals were found, including illustrations of microsections of the wood 

 showing the crystals. 



DISEASES OF PLANTS. 



Studies on Fusarium diseases of potatoes and truck crops in Minnesota, 

 G. R. BiSBY {Minnesota Sta. Bui. 181 (1919), pp. 5-58, figs. 30).— Results are 

 given of the study of Fusarium diseases of potatoes and truck crops, the in- 

 vestigations being made during the summers of 1916, 1917. and 1918. In addi- 

 tion to the I'ots of potato tubers, Fusarium diseases of peas, beans, sweet corn, 

 various cucurbits, and tomatoes were studied. 



The potato wilt, due to F. oxysporum, the Fusarium dry rot of the tubers, 

 due very largely to F. discolor sulphnrcum, and the wilts of the various truck 

 crops named above, are described. Studies were made on the effect of tempera- 

 ture, moisture, and other factors on the growth of the organisms. Results from 

 cross inoculations ai'e described, and suggestions made for control measures, 

 particularly for the prevention of potato wilt and potato dry rot. 



Cross inoculations seem to indicate that the wilt or root rot producing Fu- 

 saria may exhibit a selective tendency in their common occurrence on certain 

 host plants, although they are semiparasitic in their action, being distinctly 

 influenced by conditions unfavorable to the host plant. The isolations and 

 cross inoculations made demonstrate that no single species of Fusarium is 

 responsible for the common storage rots of vegetables, cucumbers, and tomato 

 fruits. The author claims that all the organisms produced substances in old 

 solutions that inhibited the germination of the same or other fungi. After 

 boiling, such old solutions allowed normal germination. The species of Fusaria 

 studied were found to withstand considerable desiccation and exposure to low 

 temperatures or to alternate freezing and thawing, and can utilize a wide va- 

 riety of food substances. Although many of the species are parasites, Fusaria 

 are efficient saprophytes. 



Fungus diseases [in Ceylon], T. Petch (Ceylon Ayr. Soc. Year Book, 

 1919-20, pp. 114-120). — ^This contains a general discussion of diseases and rem- 

 edies therefor in such locally occurring plants as arrowroot, artichoke, okra, 

 beans, beet, eggplant, crucifers, celery, chillies, cucumber, pumpkin, dhall 

 (pigeon pea), peanut, horseradish, mustard, pea, and tomato. 



