DISEASES OF PLANTS. 749 



rapidity and is causiiiji the dcstniclion of iar.L'e imiubiM-s of cliestinit trees iu 

 tbe infested regions. 



Snggestions are given for jireviMiting tlie further spread of the disease, whicli 

 include tlie inspection and destruction of diseased nursery stock and the treat- 

 ment of diseased trees where this is practicable. In regions where the disease 

 is widespread it is believed doubtfvd whether individual treatment will pay. 

 Where only isolated cases have appeared it is believed possible to stamp out 

 the disease by carefully cutting out and burning all diseased bark and limbs, 

 thus destroying the sources of infection. 



The diseases and parasites of cacao, F. C von Faber (Arb. K. Biol. Anst. 

 Land. u. Forstw., 7 {1909), No. 2, pp. 193-351, pis. 2, figs. 51). — A monographic 

 study is given of the plant diseases and insect and other pests to which the 

 cacao tree is subject. 



A coffee disease in Dominica {Agr. A'cu-.s- [Barbados^, 8 {1909), No. 193, 

 p. 292). — A brief note is given describing the attack of StUbella flavida on coffee 

 berries that were received from Dominica. This fungus has caused serious 

 damage in Mexico and in sevei*al South American States and is also reported 

 from Trinidad and .Jamaica. 



. Preventi\e measures are given which include the removal and destruction 

 of the affected plants, spraying, and careful attention to tillage. 



Root diseases of Hevea brasiliensis, W. J. Gallagher {Dept. Agr. Fed. 

 Malay States Bui. 2, pp. IS). — According to the author, the Para rubber trees 

 in the Malay Peninsula seem to be suffering from root diseases. An investi- 

 gation led to the identification of the cause, which is said to be due to Fomes 

 semitostus. A description of the fungus and the symptoms produced upon the 

 trees is given. 



The source of the trouble seems to be in many instances the si)read of the 

 fungus from roots and stumps of trees other than rubber. In combating the 

 disease, so far as possible all roots, stumps, and logs should be cleared away, 

 so that there will be no possibility of the mycelium spreading to the newly 

 planted trees. 



Another root disease, due to an undetermined fungus, is found occasionally 

 on Para rubber and quite frequently on camphor. The symptoms are quite 

 similar to those produced by the above-described fungus, l»ut the fungus itself 

 behaves in quite a different manner. 



A preliminary note on a branch and stem disease of Hevea brasiliensis, 

 W. J. Gallagher {Dcpt. Agr. Fed. Miilnij States Bui. (i. pp. 0. fig. I). — A l)ranch 

 and stem disease of the Para rubber seems to be quite prevalent, and a study has 

 been made of it with the result that a number of fungi have been found asso- 

 ciated with the disease, but the identification of the causal fungus has not been 

 definitely determined. 



The di.sease seems to be found on trees of all ages, and on young trees it first 

 shows itself just above the fork, generally on a branch, but sometimes on the 

 main stem. The first sign is the exudation of a black latex, and as the disease 

 progresses the branches and stems are girdled, the leaves drop, and the branch 

 is quickly killed. 



Pending a detailetl study of the cause of the disease and means for its con- 

 trol, remedial and preventive measures are suggested which consist of cutting out 

 the diseased branches and coating the wounds with tar or other material. It is 

 thought possible that spraying with Bordeaux mixture, where the attack is 

 limited to a few trees, would prove advantageous. 



Parasitic and semiparasitic nematodes occurring on plants, K. Marcinow- 

 SKI {Arb. K. liiol. Anst. Land u. Forstw., 7 (1909), \o. 1, pp. 1-192, pi. 1, figs. 



