173] 



PARASITIC FUNGI— STEVENS 



INTRODUCTION 



The notes and descriptions presented herewith are based upon collec- 

 tions of parasitic fungi made by the author mainly in the jungle of British 

 Guiana, during the summer of 1922. The collections are in no sense com- 

 prehensive since the period of time was brief and travel in the interior of 

 the country was difficult and tedious which resulted only in a sampling of 

 a small part of a very interesting territory. The collections were made 

 from five centers in British Guiana; Georgetown, the Demerara-Essequibo 

 railroad, Coverden, Tumatumari and Kartabo. 



The region of Georgetown and extending for many miles inland is flat, 

 but a few feet above sea level, and of rather monotonous flora including 

 many grasses and littoral plants, with trees bordering the rivers. 

 Pl The Demerara-Essequibo railroad, ISJ/^ miles long, extending from 

 Wismar, which is 65 mi. inland on the Demerara river, to Rockstone on 

 the Essequibo crosses a sandy upland from which the original forest has 

 been cut, but which gives considerable diversification of flora. Especially 

 at Wismar and at Rockstone where the sand hill flora merges with that of 

 the river bank is the collecting excellent. 



