NITELLOPglS OBTUSA. O 



Thames, Walton Bridge {H. Groves, 1885, once found) ; 

 Norfolk, E., Filby, Hickling, Blackfleet, Rockland, 

 Somerton, and Barton Broads, Heigkam Sound, Old 

 Meadow Dyke, Hundred Stream, etc. ; Northamptonsh., 

 canal, Northampton (H. TV. Bixon <& A. B. Jackson, 

 1905). 



First record: 'Journ. Bot.' 1881. (From Filby Broad, 

 Arthur Bennett.) 



Outside the British Isles, recorded from Sweden, 

 Finland, Russia, France, Belgium, Germany, Bohemia, 

 Italy and Northern India. 



A large, rather straggling plant, almost attaining to the size 

 of Nitella translucens, with which it was confused by some early 

 authors. The ecorticate stem and branchlets, the small number 

 •of the latter, each having but one or two nodes, the one or two 

 long thick bract-cells, and the long ultimate segments, combine 

 to produce a Nitella-like appearance, though the plant when 

 living has a distinct facies of its own. In the small size of the 

 coronula there is also a resemblance to the Nitellese, but the single 

 tier of five cells places it among the Charese. The large white 

 star-like nodes which form the most outstanding feature of the 

 plant are singularly beautiful objects. They are usually if not 

 always produced on colourless lateral branches which arise from 

 the enlarged lower stem-nodes and are immersed in the soft 

 thick mud in which the plant luxuriates. They evidently 

 represent metamorphosed whorls of branchlets, the equivalents 

 of the various parts of which are traceable. The " stars " vary 

 considerably in the length of their rays, see vol. i, p. 42, fig. 15. 

 Many of the stem-nodes and sometimes the branchlet-nodes are 

 also thickened and whitish owing to accumulations of starch. 

 Criesenhagen has carefully investigated the development of the 

 stem- and branchlet-nodes, and has elicited the fact that the 

 former are not, as Migula had tentatively suggested, less com- 

 plicated in structure than those of other Chareae. 



Through the kindness of the late Prof. Hy, we have had the 

 opportunity of examining ripe fruits, which we had not been 

 able to obtain from any of the British localities. The walls of 

 the spiral-cells are thicker and tougher than those of the other 

 British charophytes ; and the inner portions do not break down 



