A TROPICAL PYRENOMYCETOtrS FUNGUS. 347 



Researches 07i the Morphology and Life-history of a 

 Tropical Pyrenomycetous Fungus. By H. Marshall 

 Ward, B.A., Fellow of Owens College, Victoria Uni- 

 versity, late Cryptogamist to the Government in Ceylon. 

 (With Plates XXVIll and XXIX.) 



The subject of the following memoir was discovered, 

 during the wet season of 1880, in the Royal Botanic Gardens, 

 Peradeniya, Ceylon, as an epiphyte, and, as will be shown, 

 parasitic to a certain extent on the leaves of Jasminium 

 pubescens, shrubs of which are cultivated in the above- 

 mentioned gardens. At various times since I have observed 

 it on other specimens of the same plant, but so far have no 

 knowledge of its existence elsewhere. 



During the early stages of its development on the leaves, 

 the host-plant does not appear to offer any well-marked 

 symptoms of disease ; but, as the black specks of the fungus 

 spread over the leaves and other parts of the plant, suffi- 

 cient evidence of a *' diseased state " is presented to warrant 

 our regarding the presence of the parasite as the forerunner 

 of a definite plant-disease, of which it must also be con- 

 sidered the sufiicient cause. 



The healthy and normal, broadly ovate or cordate leaf of 

 the jasmine referred to, is of a soft, dull green colour, not 

 reproduced in the smaller of the two figures at fig. 1,^ which 

 represents a young leaf on which the fungus is commencing 

 to obtain a footing. The fungus itself is seen as delicate, 

 black, cloudy, or dotted patches, chiefly on the upper surface 

 of the leaf, but occurring also on the lower epidermis. As 

 these clouds and blotches become extended, or after a period 

 of persistence on a given area, the leaf turns paler, patches 

 of yellow, or yellowish white, make their appearance, in- 



^ This excellent figure was drawn by Mr. W. De Alwis of Peradeniya, 

 and I take this opportunity of thanking him for the trouble he has taken 

 in its execution. All the other figures were drawn by myself. The natural 

 colours have not been reproduced in tlie plates. 



