26 BRITISH CHAEOPHYTA. 



C. crassicauUs Kutzing Tab. Phyc. VII, p. 25, t. 60, f. 2 (1857). 

 Braitn in Monatsb. Akad. Wiss. Berl. for 1867, p. 921 (1868). 

 MiGULA Die Charaoeen, p. 614, f . 128 ? (1895) ; Krypt.-Pl. Deutsch. II, 

 ii, p. 330, t. 74, f . 1 ? (1907) ; Syn. Char. Europ. p. 133, f. 113 ? (1898). 

 C. foetida aubsp. crassicauUs Beaun & Noedstedt Fragm. Mon. 

 Oharac. p. 168 (1882). 



ExsiccATA : — Groves 17. 



Stem stout, firm. Secondary cortical-cells very thick. 

 Spine-cells short, thick and rounded at the apex. Stipu- 

 lodes very obtuse. Branchlets short, stout, incurved. 

 Posterior bract-cells usually at least twice as long as 

 broad. 



This variety in its extreme form is a remarkably distinct- 

 looking plant, characterized by the much stouter stem and 

 branchlets, the latter being incurved, the long internodes, the 

 well-developed posterior bract-cells and the botuliform stipu- 

 lodes, spine-cells and bract-cells, but intermediates occur between 

 this and other forms. Kiitzing's magnified figure shows the 

 cortical-cells as of equal thickness, but this is probably a shp. 

 Migula's figure may not belong to this variety, as the posterior 

 bract-cells are shown as rudimentary, and the branchlets are 

 not incurved. Our figure shows a rather slender form. 



The vars. longibracteata, 'papillata and refracta occur in many 

 counties ; forms referable to var. crassicauUs we have seen from 

 Hants, N., Cambs, Hunts, Warwick, Derby and Yorks, N.E. 



[C. gymnophylla Braun, closely allied to, or a sub- 

 species of, C. vulgaris, much resembles that species in 

 habit and appearance, but is distinguished by having 

 the branchlets entirely ecorticate, or with only one or 

 two corticate segments, gametangia being produced at 

 nodes from which no cortex arises. It occurs in the 

 countries bordering on the Mediterranean. We have a 

 small fragment of a plant collected by Mr. J. E. Nowers, 

 at Kilronan, Aran, W. Galway, in 1890, which appears 

 to belong to C. gymnophylla. It is desirable however 

 that further specimens should be obtained to substan- 

 tiate the record.] 



[C. Rabenhorstii Braun, having larger antheridia 

 (diam. c. 550 (j.) and usually producing oogonia and 

 antheridia at different nodes of the same branchlets, has 



