245 



It is sometimes proportionately richly branched, sometimes quite 

 branchless (Plate IX, fig. 4). The cells are roundish-polygonal and 

 without any arrangement whatever (fig. 4 b); they are apparently 

 a little smaller (lat. — 6 f^). The inner wall often seems to be thicker 

 than the outer wall (fig. 4c), it has been know nto attain to a thick- 

 ness of 3 fi. The entire thickness of the wall is about 12 ^. 



266. E. micpococca Kiitz. formå subsalsa Kjellm. Plate VIII, fig. 6. 

 Fiirthermore, in the year 1895 I found at a height of 200 — 



300 m. in a smaller stream on Gliversrejn near Thorshavn a little, 

 elegant, richly branched Enteromorpha which appears to me to be 

 very near to Enteromorpha micrococca Kiitz. formå subsalsa Kjellm. 

 (The Algæ of the Arctic sea, p. 292, tab. 31, fig. 1-3). 



Though the specimens from the Færoes differ materially in 

 one respect from this form as the transverse view shows (Plate VIII, 

 fig. 6 d) the outer wall being often somewhat thicker than the inner 

 wall, while with regard to Kjellman's form the inner wall is con- 

 siderably thicker than the outer wall, and this is also generally 

 the case with E. micrococca Kiitz. I have, however, among my 

 material of marine E. micrococca, found forms undoubtedly related 

 to this, of which sometimes the inner wall and sometimes the 

 outer was the thicker, while sometimes both walls were of similar 

 thickness. I do not therefore think that one ought to attach too 

 much importance to this character. But with this exception my 

 form seems to correspond fairly well with that of Kjellman. 



As the figure shows (fig. 6 a) it is very richly branched and pro- 

 lific. The cells are small and of a very irregular form, sometimes 

 roundish, sometimes polygonal. The outer wall sometimes attains 

 to a thickness of 3 z^; the thickness of the whole thailus varies, 

 with an average of about 11 //. 



A related form appears to be E. ramosa Boye (Algevegetationen 

 ved Norges Vestkyst p. 43, tab. 1). Its outer wall is also the thicker, 

 much more so than in my form (lat. — 6 — 8 /<), but especially in 

 the thinner branches of this species the cells are ranged in fairly 

 distinet rows. 



Order XVII. ULOTHRICACEÆ. 



267. Ulothrix zonata (Web. et Mohr) Kiitz. 



Seems to be fairly common in the Færoes as also Lyngbye points 

 out in Hydrophyt. p. 136; he mentions it as Conferva zonata. »Habitat 

 in lacubus insularum Færoensium saxis adfixa, sat frcquens.« 



