DISEASES OF PLANTS. 965 



burned and diseased pods removed from the trees. All dead trees, prunings, and 

 branches should be collected and burned, as the fungus can live saprophytically 

 upon them. The pod diseases described as occurring in Trinidad are due to the 

 fungi Pluitophthora omnivora and Neclr'm bauiii. For the prevention of injury by the 

 Phytophthora the reduction of shade, destruction of diseased pods, and spraying 

 the unattacked pods with Bordeaux mixture are recommended. The second fungus 

 so far has not proved of great economic importance. 



Of the stem diseases described the canker, due to Culonectriajkirida, is one of the 

 most important. A symptom of the presence of this fungus is the occurrence of a 

 reddish gummy liquid oozing from the bark of the stem whii-h gives a rusty appear- 

 ance to the l)ark when dry. Infection experiments have readily produced the 

 disease, and the diseased area spreading often completely rings the tree, and when 

 this is complete the tree dies suddenly. Wounds made by pruning should be coated 

 with tar to prevent the entrance of the fungus, and all trees which have been 

 destroyed bj' the canker should be cut to the ground and burned. It appears 

 2^robable that the fungus causing the rot of the pods described above occasions con- 

 siderable damage to the cacao trees by causing their <lying back at the extremity of 

 the liranches. Fertilizing and cultivation are recommended, together with the sug- 

 gestions given for the prevention of the pod rot, for the prevention of this trouble. 



A disease known as the witch-broom disease of Surinam, due to E.roascii-.t tlieobronue, 

 is described as frequently causing considerable injury. By careful attention to trees 

 and pruning out the diseased branches this can be kept in check. 



The root disease described is from an unknown cause. The trees seem to die 

 suddenly without any indication of disease in stems or branches, but the roots are 

 usually surrounded by a matted sheet of fungus filaments. The fruiting stage of 

 the fungus has never been recognized and its affinities can only be surmised. It 

 seems to have some of the characteristics i:>ertaining to the Basidiomycetes and is 

 believed to be similar if not identical with the fungus which attacks the nutmeg 

 trees of Grenada and many fruit trees in the West Indies. Where this disease 

 appears it is recommende<l that trenches should be dug about the affected trees to 

 isolate them from the rest of the plantation. A brief summary is given of the 

 general means to be adopted for combating these diseases; and a bibliography, 

 together with directions for the prei:>aration and use of Bordeaux mixture, completes 

 the bulletin. 



Fungus diseases of cacao, D. ]Morris (Bid. Bot. Dept. Jamaica, n. ser., 8 {1901), 

 No. S, pp. 113-124) ■ — An article l)y A. Howard on the diseases of cacao in Grenada is 

 quoted. The diseases described are a brown rot of the cacao pod caused by Diplodia 

 cacaoicola, canker diseases due to Xcctria tJieobromx and Culonectria favida, and a root 

 fungus which is believed to be a species of Polyporus. These diseases are described 

 at some length and suggestions given for their repression. 



Leaf curl of mulberry trees, M. Miyoshi {Bot. Centbl., 86 {1901), No. 11, pp. 

 375-378) . — According to the investigation of the author, this disease appears to be 

 caused by faulty assimilation and nutrition, brought about by improper methods of 

 culture, unfavorable climatic conditions, and varying resistance and hardiness of 

 varieties. 



Notes on Nematospora coryli, V. Peglion ( Centbl. Bnh. u. Far., 2. Abt., 7 {1901), 

 No. 21, pp. 754-761, 2^1. l). — In 1897 the author described a disease of filberts that had 

 Ijecome of considerable importance in parts of Italy. Continued ol)servations have 

 been made upon the disease, and its cause has l)een determined as due to the fungus 

 Nematospora coryli, one of the Saccharomycetes. The fungus is a parasite, and the 

 affected nuts are })itter, misshapen, and often more or less decayed. The character- 

 istics of the fungus, effect upon the host, and means of dissemination are discussed 

 at some length. The affinities of the new geims Nematospora with the other genera 

 of Saccharomycetes are shown by a key of the genera. 



