;^6 NEW YORK STATE MUSEUM 



Leaves and branches of plum trees infested by a scale insect, Leuca- 

 nium, and moistened by its secretions. Menands. September to May. 

 The insect has been doubtfully referred to Leucaniiwi Juglandis. Its 

 secretion, like that of plant lice, is probably sweetish, for honey bees 

 are attracted by it and feed upon it. This has suggested the name of 

 the fungus which develops only Avhere this secretion is deposited. The 

 fungus is separable from the smooth surface of the leaves, peehng off in 

 thin felty flakes. Its black color gives a defiled appearance to the 

 leaves and branches which is suggestive of sooty stains. Small colorless 

 globose or broadly elliptical spores are intermingled with the Coniothe- 

 cium spores in great numbers. These are about .0003 in. long. Whether 

 they constitute one form of its development or not is uncertain. It is 

 possible that they are spores of fermentation and perhaps the early state 

 of the Coniothecium. There are also the hyphae and spores of some 

 Cladosporium and Macrosporium sometimes intermingled. 



Coniothecium intricatum //. sp. 



Heaps often confluent, forming a thin continuous or interrupted black 

 crust; spores very variable, subglobose elliptical oblong or irregular, 

 .0006 to .0016 in. long, their cells few or many, subglobose or angular, 

 colored, about .0003 in. broad ; hypha3 few, short, colored, their cells 

 about as broad as long and about equal in size to the cells of the spores. 



Twigs branches and spurs of pear trees infested by the pear tree psylla 

 and moistened by its secretions. Menands. September to May. 



This fungus is closely related to the preceding one and may easily be 

 regarded as a variety of it, but there are certain differences between them 

 that have induced me to think them distinct. Chief among these is the 

 smaller size of the spore cells in the pear tree fungus. There are also in 

 company with it, and probably belonging to it, masses of small globose 

 colorless spores .00016 to .0002 in broad. These spores are smaller than 

 the corresponding spores of C. saccharinum. This fungus may be taken 

 as certain evidence of the presence of the pear tree psylla and a small 

 hand glass will often reveal the eggs of this insect on the buds and spurs 

 that are blackened by the fungus. 



SeptoglcEum Ulmi «. sp. 



Spots numerous, small, yellowish, sometimes with a brown center; 

 spores oozing out on the lower surface of the leaf and forming small but 

 prominent whitish masses, oblong or subfusiform, colorless, triseptate, 

 .0014 to .0018 in. long, .00024 to .0003 broad. 



