REVISIONS OF CEYLON FUNGI. 419 



the hymenial surface. The habit of the two species also differs ; 

 in polytricha, the fungus frequently, one might almost say 

 usually, grows witli the hymenial surface directed upwards, 

 though when growing in clusters on dead stumps, it is directed 

 upwards or downv/ards or laterally indifferently ; but tremel- 

 losa always projects horizontally from the substratum, with 

 the concave hymenial surface directed downwards. 



The great difference, however, lies in the structure of the 

 lower surface. In Hirneola 'polytricha., the hymenial surface 

 of small specimens is perfectly smooth, but in the large 

 specimens it is thro-wTi into irregular folds. This is merely the 

 expression of a more vigorous growth, and it is quite evident 

 from an inspection of the fresh specimen that these ridges are 

 merely more or less accidental folds and not a structural 

 feature. Specimens grown under a bell glass persist for several 

 months and pass from the plane to the folded form. Some- 

 times the folding or pleating involves the whole thickness of the 

 fungus. But the lower surface of A . tremellosa is furnished with 

 distinct ribs which are just as much a constant structural 

 feature as the gills of an agaric ; and there are no corres- 

 ponding depressions on the upper surface. When a pleated 

 specimen of H. polytricha is diied, the folds contract into 

 sharp ridges, and in this condition they might conceivably 

 be confused witlwthe ribs of dried A. tremellosa, but I cannot 

 imagine anyone confounding the two in the fresh state. In 

 colour, consistency, habit, and structure, H. polytricha differs 

 entirely from A. tremellosa, and Ceylon does not yield 

 intermediate forms. 



As far as Auricularia auricula judce is concerned, only 

 H. polytricha could be said to resemble that species. It is 

 similar in colour, consistency, and habit, but is apparently 

 sufficiently distinguished by its covering of white or brown 

 coarse hairs. 



For six months, I had a succession of crops of H. polytricha 

 from tea prunings buried in pots in the laboratory, but 

 although these wQve constantly deluged with water by an 

 over-zealous attendant, there was no variation in the direction 

 of Auricularia tremellosa ; some of the specimens were 6 cm. in 

 diameter. Again, both species have been grown for several 



