404 



RESEARCHES ON FUNGI 



is nothing more or less than an aborted condition {eUit avorte) of 

 Omphalia flavida. 



In 1925, Ashby,! making use of some diseased Coffee leaves 

 obtained from a valley in the Northern Range of the island of 

 Trinidad, proved by the pure-culture method that Cooke's Stilbum 

 and the Omphalia of Maublanc and Rangel do actually arise from, 

 one and the same mycelium. 



Ashby lifted ripe stilhum-hQa.d^ from a leaf-spot, washed them 



in a weak solution of 

 sulphuric acid for about 

 a minute, and then 

 placed them on corn-meal 

 agar in a Petri dish. 

 At room temperature 

 (79° r.), after three days, 

 a radiately spreading 

 growth of fine hyphae 

 had developed from most 

 of the heads, only two 

 out of ten mycelia having 

 become contaminated by 

 bacteria. Transfers of the 

 mycelium were made to 

 sterilised potato blocks, 

 rice grains, and bread. On 

 potato and rice there was 

 fair growth and reproduc- 

 tive bodies began to develop but remained imperfect and sessile. 

 On bread, however, development was completed. This substratum 

 was used by Ashby because Westerdijk ^ had recommended it for the 

 culture of Basidiomycetes. In a flask containing four parts of water 

 to one part of fresh crumb of white bread, at room temperature, the 

 mycelium spread steadily around the inoculum and, after a few 

 days, became dotted with pale-yellow Stilbum flavidum initials 

 which completed their development and formed a dense low forest 



1 S. F. Ashby, he. cit., pp. 325-328. 



2 J. Westerdijk, Report Internal. Conf. Phytopath., Holland, 1923, pp. 165-169. 



Fig. 203. — Omj)halia flavida, growing on bread 

 and water in a conical flask. In front, the 

 white bread permeated by the mycelium ; 

 above, a forest of numerous yellow gem- 

 mifers ; still higher, a group of thirteen 

 yellow sporophores towering up above the 

 gemmifers. Photographed by S. F. Ashby. 

 Slagnification, about 1 ■ 5. 



