497 
It has been observed in May and June and probably also 
later (cfr. Simmons, 1. c. p. 272), and found with zoospores in 
the same months. 
Found in the following places: — Bord6: Klaksvig ||| 0st.: Ejde(!); 
Vaago: Midvaag®; Str.: Thorshavn (!).; Naalso(!);? Syd.: Klaksvig 
(Simmons). 
ULVA (L.). 
169. II. Lactuca L. Lyngb., Hydrophyt., p. 30; Kjellman, N. I., 
p. 361 (293). 
A transverse section of the thallus shows that the cells vary 
much in form, being sometimes short, about as long as broad, 
sometimes long and narrow, and in this the latter examples come 
very near to Ulva crassa Kjellm. (1. c. p. 293); one of my reasons 
for mentioning this here is, that Simmons (1. c. p.273) regards 
some specimens gathered by him in Trangisvaagfjord as belonging 
unquestionably to the latter species. I have not seen Simmons’s 
specimens, but it appears to me that my specimens should pro¬ 
perly be referred to Ulva Lactuca , with which species Ulva crassa , 
as Kjellmann himself (1. c.) also pointed out, is very closely allied. 
Lyngb ye (1. c.) describes a var. ft contorta of this species as 
follows: — »fronde basi attenuata, spiraliter contorta, crassa, deinde 
in plures lacinias dilatatas profunde fissa«. His herbarium contains 
a specimen from Thorshavn. 
This species occurs in the sublittoral zone and is met with 
from about low-water mark down to a depth of some 10 fathoms. 
In N. I., Kj ell man says that this species grows in the littoral zone 
along the Norwegian coasts of the Arctic Sea and it is conse¬ 
quently perhaps possible that it also occurs littorally along the 
coasts of the Faeroes. It has been found on sheltered as well as on 
exposed coasts and grows on rocks and stones and more rarely as 
an epiphyte on larger algse. Large vigorous plants occurred from 
May to December, and fruiting examples from May to July and 
in October. 
This species is quite common along the coasts of the Fseroes. 
Order ULOTHRICACEAE. 
ULOTHRIX Kiitz. 
170. U. flacca (Dillw.) Thur. Rosenv., Gronl. Havalg., p. 935; 
Wille: Studien uber Chlorophyceen, p. 18, tab. I, figs. 54—57, tab. II, 
