OBSPTRVATIONS ON THE VEGETATION OF THE ANTARCTIC SEA 253 



The regional distribution of the marine flora. 



Accordint^ to my observations on Antarctic al^a; the classification 

 of Kji:i.i..M AN ' into three rej^ions, littoral, sublittoral and elittoral may 

 be used (K|i;i.i.M.\\ first used the word Gebiet- instead of >Re<(ion»). 

 Other autlioi's have a somewhat different opinion. It seems to me 

 natural that the tide must be of decisive importance for the limitation 

 of the littoral region. Rf )SK.\\ INCH ' puts the upper limit where ve<^e- 

 tation begins, and this according to him is at hii^h water mark at neap 

 tide; and the lower boundar}' then will be found at the correspondintj 

 low water mark. i'Or the h\'eroes B<)R(iESK\^ appro\'es the same limi- 

 tation. I am not able to decide if these limits can be used in the 

 Antarctic too; I am oblii^ed to follow the rou<;h definition, i. e. littoral 

 region ^- the space between hii^h and low water. 



The sublittoral region extends according to Kjl-.I.I.MAX ^ to a depth 

 of 20 fathoms, then begins the elittoral. RoSENVlXc;!". (1. c. p. 237) 

 proposes to mo\'e the lower boundar\' down to the dei)th, in which 

 the macroscopic flora ceases; consequently the elittoral region supports 

 no such vegetation. RORC.ESKN (1. c. p. 749) is of the same opinion. 

 Concerning the conditions in the .Antarctic Sea I will keej) tc^ the okl 

 boundary, because of the /^rj";//(7/rj."//V?-formation which characterizes the 

 sublittoral region in its old sense. I propcjse 40 — 50 meters as the 

 lower limit. Still deeper we find some spots with alg.'e, belonging 

 to an elittoral region. 



The littoral region. 



As mentioned above, this region is exposed to very pernicious in- 

 fluences and is for the most part devoid of vegetation, just as accord- 

 ing to KjKl.l.MAN ' in the Arctic Sea. On sheltered coast we tind a 

 rather rich flora, at least on indixiduals, that seems to me superior 

 to that of Arctic, except on the coasts of (jreenland and in .Arctic 

 Norway. Certainly the tracts laid dry at low water, are not very rich, 

 but the numerous lagoons, pools and caves, where some water is always 



' Alg. Murm. Meer. p. 57. 



'^ Om algevegetationen ved Cironlands kvster ;Meddel. om (ironland. XX. Koben- 

 havn 1898), p. 189. 



' The algx'-vegetation of the l"a;rücse coasts. H^otanv of the Fivroes. III. Koben- 

 havn 19O)), p. 709. 



* Alg Murm. Meer., p. 57, Alg. Aret. Sea, p. 8. 



* Alg. Aret. Sea, p. 9. 



