CALOTHRIX. 243 



itself In a distinct genus, and perhaps this would have been 

 the correct course ; It Is, however, more naturally associated 

 with the genus Tolypothrix than with Scytonema. It forms 

 little tufts two or tlu'ee lines in height. 



28. CALOTHRIX. 



Char, Filaments of equal diameter , branched by apposition. 

 Derivation. From koXos, beautifid, and 6pi^, a hair. 



1. CALOTHRIX MIKABILIS. 



Plate LXIX. Fig. 1. 



Char. FUaments tufted, aruginous, black, articulated. Stria? 

 distant about the half of a diameter from each other, dis- 

 tinct. 



Conf. mirabilis DIllw. t. 96. Calothrix atroviridis Harv. 

 in Manual, p. 159. ; Harv. in Hook. B. Flora, p. 369. 



Ilab. On mosses and in small streams, rare. Stream 

 which runs through the wood at Penllegare, near 

 Swansea: Dilhcyn. — C. atrovii'idis in spring wells, near 

 Penzance : Mr. Ralfs. Aberdeen : Dr. Dickie. 



Having had oiDportunltles of examining, through the kind- 

 ness of Mr. DHlwyn and Mr. Harvey, authentic specimens of 

 Conf mirabilis and Calothrix atroviridis, I have no hesita- 

 tion in declaring that the two plants are identical. There 

 is a close resemblance between C. mirabilis and Lyncjbya 

 copulata, which species ought not to be far removed from each 

 other in a natural arrano-ement. 



R 2 



