470 



Faciis in flat us f. edentata can grow in fairly exposed piaces and 

 it can grow rather near high-water mark ; but the higher the habitat 

 and the more exposed the locality, the smaller the specimens. On 

 the east coast of Stromo from Thorshavn southwards I have dis- 

 tinctly observed this transition in process. Large vigorous examples 

 of f. edentata occurred in the two small bays at Thorshavn at about 

 low-water mark (the specimen figured in fig. 90 is from the latter 

 locality). To southward of this the coast gradually grows more ex- 

 posed, there is almost always sorae swell and the waves break 

 almost continuously upon the shores which both enables Fucns 

 inflatns to grow higher up and al so reduces its size. On a gently 

 inclined rock-face south of Arge I observed for the first time inter- 

 mediate forms in different stages which distinctly illustrated the 

 transition from f. edentata to f. disticha. The piants growing near 

 low-water mark were fairly large, about one foot in length, but 

 as they spread higher up the face of the rock they gradually 

 grew smaller in all their parts until at the top at about high-water 

 mark or somewhat above they were only a few inches long, or, in 

 other words, occurred as Fucus distichus; while still further south- 

 wards the coast becomes too exposed for f. edentata, and f. disticha 

 only is met with. The latter form of Fncns inflatns is fonnd in 

 the most exposed localities along the Færoese coasts, often in large 

 quantities and frequently at a considerable height above sea-surface. 

 The more exposed the locality, the more vigorously developed is 

 its attachment-disc, which in specimens measuring 2 — 3 inches in 

 length often attains to a size of 1 /2 an inch in transverse section; 

 and the more graceful and elegant are its branches, while its 

 receptacles also grow longer and more pointed, such particularly 

 elegant specimens (fig. 93) were found by me, e. g. on Myggenæs, 

 Muletangen, Vaags Ejde, Sumbo Holm., etc. 



While f. disticha always occurs on sloping rock-surfaces left 

 dry at ebb-tide, f. linearis occurs between tide- marks in pools at 

 high-Ievels. Situations adapted to the growth of this form seem lo 

 be rare along the Færoese coasts. I have hitherto only found it 

 near Famien on Sydero. The Færoese specimens agree very well 

 with the somewhat broader ones from Greenland which Rosen- 

 vinge has referred to this form; I have not come across any 

 Færoese specimens which were quite thread-shaped. Formå linearis 

 is distinguished from f. disticha by its branches being thinner and 

 more Hat, the colonr nsually somewhat paler and the shoots Irans- 



