486 
appears to differ somewhat from this species and it is perhaps 
doubtful whether it belongs to it at all (cfr. Rosenv., Gronl. Havalg, 
p. 938, and Wille, Faeroernes Ferskvandsalger, p. 53). 
With regard to its habitat Wille writes (1. c. p. 14): — »Sie 
wuchs auf der Scliattenseite am hochsten Wasserstandszeichen, so 
dass sie nur bei Springflut oder starken Wellenschlag von Salz- 
wasser benetzt werden konnte, und deshalb abwechselnd der Durch- 
netzung mit Salz- und Regenwasser ausgesetzt war.« This corres¬ 
ponds in the main with its distribution along the sheltered coasts of 
the Faeroes, while along the open coasts, according as the place 
is more or less exposed, it occurs from several feet above high- 
water mark to upwards of at least 40 feet above it. Nor does it 
grow here exclusively on the shady sides of the rocks, but it also 
occurs in open places facing south and exposed to the sun. Conse¬ 
quently, it is often quite dried, and naturally enough in such habi¬ 
tats it is also often liable to be wetted only by freshwater for a 
longer period at a time. 
This species has been observed along the coasts of the Faeroes 
in the summer and autumn months and doubtless occurs there all 
the year round. 
It is presumably very common along the coasts of the Faeroes, but 
is often difficult to gather off the steep rocks; it has hitherto been 
found in the following places: — Svino(!); Videro: Kvannesund (H. J.); 
0st.: Skaalefjord (H. J.); Str.: between Hojvig and Skandsetangen (!), 
Gliversnses (!); Lille D i m o n (!). 
subspec. terrestris (Roth). Ulva terrestris Roth. Lyngb., Hydro- 
phyt., p. 32. 
This is recorded from the Faeroes also as a marine alga by Lyng- 
bye (1. c.), who writes: — »In insulis Fseroensibus in terrestribus 
umbrosis humidis, et ad rupes marinas paulo supra littora, aeri 
marino exposita.« The specimen collected by Lyngbye and pre¬ 
served in the museum in Copenhagen is from Ridevig, 0stero. In 
Tliorsliavn and its environs I have also found Prasiola crispa grow¬ 
ing in places where it is frequently liable to be wetted by the 
spray, so that there is good reason to regard it also as a marine alga. 
160. P. furfuracea (Mert.) Menegh. Lagerstedt: Om algslagtet 
Prasiola, p. 31; Imhaiiser: Entwicklungsgeschichte und Formenkreis 
von Prasiola (Flora 1889, p.266); Foslie, Contrib. I, p. 127. 
Found on rocks along the shore where it is completely washed 
by the waves when the sea is rough. The specimens agree well 
