54 



margins of the hot springs of Iceland, fully exposed to the 

 influence of steam and boiling water — they consisted principally 

 of Oscillatoria and species of Confervse. Dr. Hooker in his 

 Himalayan Journal describes Confervas as present in the hot 

 springs of Belcuppee. He says — " Confervse abound in the 

 warm stream from the springs and two species, one ochreous 

 brown and the other green, occur on the various margins of 

 the tanks themselves and in the hottest water ; the brown is 

 the best Salamander and forms a belt in deeper water than 

 the green ; both appear in broad luxuriant strata, whenever 

 the temperature is cooled down to 168° and as low as 90*'." 

 On the same expedition Dr. Thomson and Captain Strachey 

 found Algse in the springs of Pugha in Tibet, which attain 

 a temperature of 174", and at the hot springs of Mormay, 

 with a temperature of 110°. The Eev. J. M. Berkeley, who 

 examined these specimens, says of them : — " The vegetation 

 in the three sets of springs was very different. As regards the 

 Confervas, taking the word in its older sense, the species in the 

 three are quite different, and even in respect of genera there is 

 little identity ; but amongst the Diatomaceae there is no striking 

 difference except in those of the Behar springs, where three out 

 of the four did not occur elsewhere. In the Pugha and Mormay 

 springs the species were either identical with or nearly allied to 

 those found in neighbouring localities, where the water did not 



exceed the ordinary temperature The species are 



less numerous than might be supposed from the 



vegetation of those European hot springs which have been most 

 investigated." 



In America, Horatio Wood describes two new species of Algse, 

 Nostoc calidarium, and Chroococcus thermophilus, found in the 

 hot springs of Benton, California, the temperature of which is 

 160°; and in the reliowstone River district are some remarkable 

 boiling mud springs which are coloured bright green by the mul- 

 titude of Algte contained in them — this observation was made by 



