33 



OBSERVATIONS ON THE BIOLOGY OF SOME 

 SAND-DUNE FUNGI. 



By E. M. Wakefield F.L.S. 



The following notes were for the most part made during 

 July 191 7, on some species of Agarics found growing on 

 sand-dunes near the village of Oxwich, on the Gower coast, 

 vSouth Wales. V'ery little work has been done on the fungus- 

 flora of sand-dunes, though Wheldon's list of the fungi 

 of the Lancashire dunes* shows how surprisingly large this 

 fungus-flora may be. It has been thought worth while to 

 place these few observations on record, as offering some 

 suggestion as to the means by which delicate Agarics manage 

 to exist in what is apparently so unfavourable a habitat. 



Psilocyhe ammophila Mont. 



This species, which is absent from Wheldon's list, occurs 

 abundantly on the Gower dunes in the summer months, 

 after rain. It grows on the exposed slopes of high dunes, 

 usually about the tufts of Marram grass {Ammophila 

 ariindinacea). When dug out the stem appears to be 

 clavately swollen below, and continued downwards as a 

 tapering, rooting base. As a matter of fact the stipe itself 

 is of equal diameter throughout, as may be seen in a 

 vertical section, and it terminates abruptly an inch or so 

 beneath the surface of the sand. The apparently clavate 

 lower half, and the long root-like base are due to a weft of 

 fine hvph^e mixed with particles of sand, which surrounds 

 the buried part of the stem, and is continued downwards 

 as a gradually tapering cord. This cord, however, is very 

 different in structure from an ordinary mycelial cord. Con- 

 sisting merely of loosely interwoven hyphaj, the interstices 

 being filled with sand, it is extremely fragile, and hence 

 difficult to trace to its point of origin. 



After many attempts to dig out the underground 

 portion of the fungus, I was at length able to satisfy myself 

 that it is always connected with buried, decaying leaves of 

 the Marram grass. Only occasionally, however, does it 



*H. J. Wheldun in Lancasli. and Chesli. Naturalist, 1914. 



