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THE FLORA AND FAUNA OF NUYTS ARCHIPELAGO AND THE 

 INVESTIGATOR GROUP. 



No. 14— THE BASIDIOMYCETOUS FUNGI OF PEARSON ISLAND, 

 GREAT AUSTRALIAN BIGHT. 



By J. Burton Cleland, M.D. 



[Read October 11, 1923.] 



Considering that the visit of Professor Wood Jones' party to Pearson 

 Island was in the middle of summer (January, 1923), and had been preceded 

 by a long spell of dry weather, and that, as far as fresh water is concerned, this 

 island is practically waterless, the utmost that could be expected was that a few 

 woody bracket fungi and dried pulT-balls might be found. No idea would be 

 obtained of the species of fleshy agarics and of delicate, more ephemeral kinds 

 that doubtless are to be met with during the wet season. These expectations 

 were realized. These records, therefore, in no way indicate, as far as concerns 

 the higher fungi, the floral potentialities of this island. 



The spores of the higher fungi, in many cases liberated in millions from 

 the fruiting bodies, may, according to Buller (Researches on Fungi), take about 

 half a minute to fall an inch in a perfectly still atmosphere. When currents of 

 air catch them, they may remain almost indefinitely suspended, according to the 

 direction of these, and may be wafted hither and thither, doubtless over enor- 

 mous distances. In this way the spores probably of many species on the 

 adjacent and even distant parts of the mainland of Australia get carried into the 

 upper regions of the atmosphere and may be directed by favourable winds to 

 this small island 40 miles from the coast. To germinate and establish themselves 

 they require the particular organic menstruum necessary to them, as well as suit- 

 able conditions of warmth and moisture. Of the spores of many species reaching 

 the island, few are likely to find the exact conditions they require. In this 

 connection, it was interesting to find the presence of the bracket fungus, Poly- 

 poriis decipiens, a purely Australian species found growing on dead or living 

 Casuarina wood, and rarely, if at all, on the wood of other genera. Here, 

 again, it was met with on the dead wood of C. stricta, Ait. 



But, apart from wind dispersal and from the accidental introduction of 

 spores attached to the clothing and other accompaniments of the few human 

 beings who have visited this island, there is another way by which the presence 

 of certain fungi may be explained. They may represent the descendants of 

 species occupying this area of land when it was separated, ages ago, from the 

 mainland. It is impossible to suggest that any particular species found, more 

 than another, had such an origin — all, some, or none may have been so derived. 



Two polypores and a Corticium represent the only members of the 

 Hymenomycetes found. 



Amongst the Gasteromycetes, there were four species of Geaster, a rounded 

 Polysacciim, a Lycoperdon, and a Catastoma. Of particular interest was the 

 finding of Geaster fornicatus, arising from a mass of whitish mycelium binding 

 together fragments of soil and vegetable debris, in exactly the same way as in 

 specimens from Mullumbimby, in New South Wales, found by the writer. The 

 only other additional locality in which I have found this species was near Hallett's 



