' MYCETOZOA OF CEYLON. 326 



found only in low-country jungles and rubber plantations in 

 the wettest district. 



During the first three months of the year, in which the total 

 rainfall (at Peradeniya) is about 9 inches, Mycetozoa are 

 practically absent. The heavy showers of that period run off 

 the surface of the leaf heaps without wetting more than the 

 outer layer, and fail to penetrate the dead stumps. In April 

 a rainfall of about 9 inches rouses Diachcea elegans and 

 Didymium effitsum. and thencefoi-ward there is a constant 

 harvest until the end of the year, the diminution of rainfall in 

 August and September being insufficient to check growth. The 

 greater rainfall and humidity produce two results which appear 

 abnormal to one who has collected Mycetozoa in Europe, viz., 

 the greater tendency of the plasmodium to " wander " and the 

 greater height from the ground at which species are found. 

 Diachcea elegans, Diachcea subsessilis, Physarum gyrosum, and 

 Stemonitis herbatica apparently always have the wandering 

 habit, but in Ceylon it is occasionally found in Stemonitis 

 fusca, Craterium pedunculatiim , Physarum calidris, Didymiiim 

 effiisum, and Didymium nigripes also. Craterium peduncula- 

 tum, Didymium effusum, and Physarum calidris have been 

 collected on green stems of Strobilanthes , having apparently 

 chmbed up after the manner of Diachcea, while the other 

 two species have been found on earth and stones in flower 

 beds and gravelled footpaths. Stemonitis herbatica, Physarella 

 mirahilis, Didymium effv^um, and Cribraria intricata have 

 been gathered from the crowns of palm trees, 20 feet from 

 the ground, and Stemonitis splendens at about the same 

 height on rotten mango branches. Perichcena chrysosperma 

 might almost be said to adopt such a habitat normally ; it 

 is frequently found on rotten Bombax branches which have 

 fallen from a height of some times over 50 feet. Of course, 

 these statements are based on cases in which the branch 

 has been seen to faU, and has been examined immediately 

 afterwards. After such examples it wiU be understood that 

 dead erect tree trunks or the dead leaf bases on the stems 

 of living palms are always worth examination, and, up to 

 a height of 10 feet, provide almost as many species as dead 

 trunks lying on the ground. Chondriodermu rugosum and 



7(12)09 (43) 



