170 fl> o s t e l s i a 



balls, Nostoc verrucosum. Before going 

 back to the horses we gathered speci- 

 mens of eight or ten new ferns, among 

 them Psilotum triquetrum, and some 

 tree lobelias, shrubs three to six feet 

 high, with very large flowers. 



July 17th found us back in Hilo, and 

 we were soon on our way to Puna dis- 

 trict, where we wished to work in the 

 vicinity of Green lake. The house 

 and grounds of our host occupied the 

 level crater of an extinct volcano, now 

 completely carpeted with grass. In a 

 second crater, quite near to the first, 

 was the sheet of water known as Green 

 lake. In this there was found to be 

 but little except a few desmids and 

 Cladophoras. We had heard of a 

 warm spring in this neighborhood, and 

 the next morning made a search for it. 

 The water was not particularly warm, 

 being only 31 C. at the time we took 



