224 KJELLMAN, THE ALG OF THE ARCTIC SEA. 
rences between these alge, leaving it undecided whether these are differences of species 
or of age. However, in bidrag till kdinnedomen om Spetsbergens Alger, Tilligg, he 
seems to have abandoned his earlier view and to regard the alge in question as different 
forms of the same species. His description may be applied to both of them. In my 
works on the marine vegetation at Spitzbergen and in the eastern Murman Sea I have 
adopted the latest view of J. G. AGarpu and accordingly referred all the Phyllaria 
occurring in those regions to one and the same species, Saccorhiza dermatodea. I must 
now relinquish this opinion. After having seen on the coast of Finmarken a great. 
number of Phyllariw in different stages of development and having, en account of the 
observations I made there, again carefully examined my collections from other parts of 
the Polar Sea, I have arrived at the conclusion that there exist in the Polar Sea two 
species of Phyllaria, the one identical with the plant recorded by J. G. Acarpu (Spec. Alg.), 
J. E. Arescnuoue, and Farntow as Laminaria (Saccorhiza) dermatodea, the other identical 
with Laminaria lorea J. G. Ac. I have been compelled to this opinion most of all by 
the fact that even among very young plants — what might almost be called germinat- 
ing plants — there are to be observed two sharply distinct species. In some the stipe 
is longer, more or less distinctly marked from the lamina, the lamina is oblong, ovato- 
oblong or broadly lanceolate, darkbrown in colour, only little translucent, with very 
few short-haired cryptostomata. These are young plants of Phyllaria dermatodea. The 
young plants of the other species — I possess such plants in considerable number from 
Spitzbergen as well as from the west coast of Novaya Zemlya — have a very short 
stipe passing without definite limit into a narrow, sometimes almost filiform, linear, or 
more usually lanceolate lamina. Their lamina is thin, very light brown, almost yellowish- 
brown, perfectly pellucid with numerous long-haired cryptostomata. These plants be- 
long to the alga described by J. G. AGArpn under the name of Laminaria lorea, which 
even when older has the same shape and colour of the lamina as the young plants and whose 
lamina is pellucid with numerous cryptostomata. Older specimens of the two species are 
easily distinguished from each other by several good characteristics. In Ph. lorea the 
stipe collapses in drying, and becomes flat, thin, almost membranaceous, and brittle; 
even in very large specimens it has the same colour as the lamina, being pellucid like 
this. In older specimens of Ph. dermatodea the stipe is far more solidly built, dark- 
brown, opaque, flat upwards, but almost terete downwards. With this outward differ- 
ence of the stipe there is connected a difference in its structure, which, as far as my 
observations go, is essential and lasting during the whole life of the plant. In Ph. 
dermatodea the stipe is composed of 1:0 a layer of cortical cells which are square or 
tangentially rectangular in transverse section, very rich in endochrome, with the outer 
wall cuticulated; 2:0 inside this a thick layer of large thin-walled cells which increase 
inwards in length and also in width, and farthest in are several times longer than wide; 
3:0 a central layer formed of almost isodiametrical cells of different sizes and with 
thinner walls than the cells of the middle layer; 4:0 very long tubular cells, with very 
thick walls, sometimes simple, sometimes branched, which in transverse section are seen 
to be arranged circularly on the limit between the middle and the central layer. These 
tubular cells occur even in very young individuals though in little number, but become 
