138 M - Foshe. 



ler, usually 4 — 6 cm. long, of a rather dark green colour, 

 robust, densely branched, sometimes forming roundish balls, 

 and in the lower part of the frond often very coarse with 

 thick cell-wals. I have distributed this form under the na- 

 me of CI. gracilis f. borealis. But as yet I am uncertain 

 whether it may be regarded more than a local variety of 

 the species. The plant is generally smaller along the north- 

 ern coast of Norway than more south. However I have 

 seen British specimens determined by Harvey which al* 

 most fully coincide with Finmarkian ones of the normal 

 form. On the other hand the species sometimes approaches 

 nearley to CI. glaucescens. Cp. Wittr. et Nordst. Alg. 

 exsicc. Nr. 620. 



The present species is litoral and grows in pools in 

 the upper part of the zone. It occurs both on open and 

 sheltered coasts, but it seems to prefer protected places. 

 Specimens with zoospores have been collected in August. 



Distribution: Pretty common along the whole coast 

 and at serveral places plentiful. 



Gen. Rhizoclonium Kiltz. 

 Phyc gener. p. 261. 



Rhizoclonium riparium (Roth) Harv. 

 Phyc. Brit, t 2S8; Conferva riparia Roth, Cat. Bot. 3, p. 216. 



f. typica "Wittr. 



in Wittr. et Nordst. Alg. exsicc. Nr. 623. 

 Descr. Rhizoclonium riparium f. typica Wittr. 1. c. 

 Fig. „ „ Harv. Phyc. Brit. t. 238. 



Exsicc. „ » Wittr. et Nordst. 1. c. 



Cfr. Conferva implexa Aresch. Alg. Scand. exsicc. Nr. 136. 



f. valida Fosl. 



in Wittr. et Nordst. Alg. exsicc. Nr. 624. 

 P$ser, B^hizocjonium riparium f, valida Fosl, l f p, 



