191] PARASITIC FUNGI— STEVENS 25 



side (Figure 58). The spot surrounding the stroma is also uniform and since 

 no mycelium could be found outside of the stroma it is probably due to 

 chemical rather than mycelial invasion. The specimens bear also a 

 Myrianginella. 



MONTAGNELLACEAE 



EU-MONTAGXELLEAE 



Haplothecium Theiss. and Syd. 

 Ann. Myc, 13:614, 1915. 



31. Haplothecium guianense Stevens n. sp. 

 [Figures 60 to 62, 104.] 



Stromata 1 to 2 mm. in diameter showing from above and below, black, 

 subcircular, surrounded by a very narrow (0.5 mm.) brown line, this by a 

 zone 1 to 2 mm. wide that is pink to rose which gradually shades off into 

 healthy tissue. Stroma occupying the whole mesophyll, consisting of a 

 very loosely woven mycelial network with a black clypeus in both upper 

 and lower epidermis. Locules globular to pyriform, ostiolate, in two rows 

 opening through the upper and lower epidermis, 170 to 260/i. in diameter. 

 Asci 8-spored, 100 .x 18/i, uniseriate or inordinate. Paraphyses filiform, 

 gelatinous. Spores oval, 12 x 7/j, hyaline, continuous. 



On unknown lactiferous dicotyledonous leaf (Simarubaceae?). 

 British Guiana: Demerara-Essequibo R. R., July 15, 1922, 376. 



The stroma in the mesophyll consists only of a very loose hyphal net- 

 work mainly occupying the intercellular spaces. In the palisade region 

 the mycelium presses between the cells and kills them but no compact 

 stroma develops. The epidermal cells, however, are compactly filled with 

 mycelium thus forming a clypeus. 



The loose hyphal character of the stroma clearly shows relationship to 

 the Montagnelleae in which the fungus would fall in the section Eu- 

 montagnellaceae and in the genus Haplothecium Th. and Syd. where it 

 would certainly be placed were it not for the presence of an epidermal 

 clypeus. This clypeus would indicate that it should be placed in the Phyl- 

 lachoraceae where it could only fall in the genus Phyllachora. Since the 

 fungus all in all agrees more closely with Haplothecium than Phyllachora 

 I place it as above indicated. 



HEMISPHAERIACEAE 



Gymnopeltineae Stevens and Guba mss.' 

 Gymnopeltis Stevens n. gen. 

 Ascoma like the Thrausmatopeltineae but red and with asci solitary, 

 scattered: spores unequally 2-celled, hyaline. 



' Publications of the Bishop Museum, in press. 



