DISEASES OF PLANTS. 49 



tei-ior of the lemons and produces black sclerotia, and the ascospore stage which 

 is developed from the sclerotia. These spores on germination may infect either 

 the cover crop or the green lemons through the button end through some abra- 

 sion on the fruit. The cottony mycelium thus produced is capable of infecting 

 perfectly healthy lemons. 



It is stated that the disease has increased with the increased growing of 

 cover crops, especially vetch, as the dense growth of this legume affords a suit- 

 able place for the development of the fungus, which also occurs as a saprophyte. 

 Under the vetch the sclerotia are produced in great numbers on any dead or 

 dying vegetable matter, and on the advent of the winter rains develop the spore 

 stage. It is also claimed that the fungus is actively parasitic on the twigs 

 and branches of both lemon and orange trees, where sclerotia are produced 

 with spores capable of infecting the green lemons, but that by far the worst 

 and most common method of infection is from the clover crop. 



It is suggested that the most logical method of combating this disease is in 

 the washing tank by using some strong disinfectant, such as copper sulphate, 

 but that further experiments are necessary before an exact formula can be 

 given. 



Bloom blig'lit of mango in Cuba, P. P. Cardin [Cuha Rev., 8 (1910), No. 5, 

 pp. 28, 29, fig. 1 ) . — Attention is called to the prevalence of this disease ( Glceos- 

 poriuni nmngiferw) in Cuba, which causes the opening blossoms of infected trees 

 to turn black, rot, dry up, and fall off, this being followed by the withering and 

 death of the central stem. Insects which visit the flowers carry the spores of 

 the fungus from flower to flower, thus spreading the disease. Two thorough 

 applications of Bordeaux mixture at intervals of 2 weeks are recommended as a 

 remedy. 



A new disease of the olive, L. Montemartini (Riv. Patol. Vcg., 4 {1910), 

 No. 11, pp. I6I-I6J1). — The author describes a disease of olives which first causes 

 the extremities of the foliage to wither. As the disease advances, the interior 

 of the branches are invaded until finally the tree dies. 



On removing the bark of an attacked branch, the cambium zone shows a 

 brown color, which becomes more intense as the disease progresses, and finally, 

 especially in young plants, becomes putrid and watery, thus preventing the 

 movement of the sap. Associated with the diseased areas was found an abun- 

 dance of a large bacterium which is supposed to be the cause of the disease, and 

 which will be described in detail in a later paper. The disease begins appa- 

 rently in the very young branches, and spreads from these to the larger and 

 older parts. 



The Phytophthora rot of pears in Bohemia, F. Bubak (Ztschr. Pflanzcn- 

 Jcrank., 20 (1910), No. 5, pp. 257-261, pi. 1, figs. 2).— The author describes the 

 characteristics, mycelium, and fructifications (conidia and oospores) of this 

 fungus (P. cactorum) as found in the ripe or ripening fruit of pears. The 

 mycelial threads are nonseptate, and usually without haustoria, the usual char- 

 acters of the mycelium for this fungus when it is living saprophytically. 



A disease of the grape, J, V. Solano (Bol. Dir. Fomento [Pent], 8 (1910), 

 No. 5, pp. 1, 2, pi. 1).—A disease of the grape which causes large tumors or 

 excrescences on the stems is reported from the Moquegua Valley as doing great 

 damage. The direct cause of this disease is not known, but It is supposed to be 

 of a bacterial nature and is apparently worse after a winter of low temperature. 



Cutting out the diseased areas, washing the wounds with a solution of sul- 

 phate of iron (50 kg. sulphate of iron, 1 liter sulphuric acid, and 100 liters 

 water), and then covering them with tar or clay, is the remedy recommended. 



A vine disease of lower Austria, L. Linsbaxjer (JahrcKhcr. Ver. Angeio. Bot., 

 7 (1909), pp. 112-118, figs. 5).— A general discussion is given of the character- 



