R. H. SCHOxMBURGK. 41 



a spring, when one of the guides, going up to a 

 ligneous twiner which wound itself snake-like round 

 one of the trees, called out " Ourali !" the name of 

 the plant in question in the Wapisiana tongue. 

 This is a ligneous vine ; its stem, often more than 

 three inches thick, and crooked; its bark rough, 

 and of a grey colour ; the leaves dark green, oppo- 

 site, ovate, acute, five-nerved, veined, and hirsute ; 

 young branches also hirsute ; fruit of the size of a 

 large apple, round, smooth, bluish-green ; seeds im- 

 bedded in a pulp, and consisting chiefly of a gummy 

 matter which is intensely bitter. It grows only in 

 one or two places in Guiana, which are resorted to 

 by Indians from all directions, and often from great 

 distances. It has been ascertained to be a species 

 of Stri/chnos, and has been named Strychnos toxi- 

 fera^ Schomb. 



Having descended to the savannahs, and follow- 

 ing the course of the Rupununi, the party returned 

 to Pirara. In the month of April the savannahs 

 on this side of the Rupununi are completely inun- 

 dated ; the waters of two rivers belonging to two 

 distinct systems, swollen by the rains, are said by 

 the Indians to commingle at tliat period, and the 

 deluge thus realized has doubtless given rise to the 

 fable of the Lake Paraima. 



Many of the savannahs are covered with the 

 fabrics of a species of termites; these are pyra- 

 midal, from five to ten feet high, and formed of 

 ochreous clay. Another species of this insect en- 

 crusted the trunks of trees from the base to the 



