KONGL. SV. VET. AKADEMIENS HANDLINGAR. BAND. 20. N:O 5, 257 
f. reniformis nob. 
f. lamina reniformi, in lacinias numerosas usque ad basim digitato-fissa; lacunis muciferis stipitis nume 
rosissimis in orbem regularem infra stratum corticale dispositis. 
«. longipes nob. 
f. stipite longiore usque 1—2 pedali, infra apicem complanato; laciniis lamina numerosis, sat latis 
Forma a J. G. AGARbuLO descripta. . 
2. brevipes nob. 
f. stipite brevi, 2—6 pollicari; laciniis numerosissimis, angustis. 
f. oblonga nob. 
f. lamina late oblonga, basi sepe obliqua, integra vel in lacinias latas, pauciores plus minus profunde fissa. 
«&, compressa nob. 
f. stipite longiore usque tripedali, superne compresso, swpe infra apicem valde complanato; lacunis mu- 
ciferis stipitis irregulariter infra stratum corticale dispositis, paucioribus, magnis. 
P. subteres nob. 
f. stipite breviore, subterete; lacunis stipitis minoribus, numerosis infra stratum corticale in orbem fer: 
regularem dispositis. 
Syn. Laminaria digitata f. latifolia KyeLum. Spetsb. Thall. 2, p. 26. 
» » forma KyeLuM. |. c. p. 26—27. 
» » f. typica (vera) Kortum. Algenv. Murm. Meer. p. 38 et Kariska hafvets algv. 
p. 25; ex parte !). 
» » KJELLM. Vinteralgv. p. 64; ex parte. 
Remark on the species. In the collections of arctic algw that I have had the 
opportunity of examining, there is to be found a Laminaria of the digitata group taken 
in different parts of the Arctic Sea, which I have formerly confounded with L. jlevicaulis 
Le Jon. and recorded under the name of ZL. digitata. J. G. AGaRpu has separated it 
from L. digitata and described it as L. nigripes. By a more anatomical investigation 
of a greater number of Laminariw from different regions I have arrived lately at 
the conclusion that the structure of the lamina and the presence or absence of muci- 
ferous lacune in the various parts of the frond ought to be accounted more important 
in distinguishing the species of this group of algw, than I supposed formerly, relying 
on the authority of J. G. Acarpu. Consequently I must acknowledge L. nigripes 
as a well differentiated species. It resembles closely L. digitata (L. jlevicaulis Le 
Jou.) in habit and possesses a series of forms similar with this, but in structure it 
accords more nearly with ZL. Clustont Ly Jou. As in this species, there are muci- 
ferous lacune in the stipe, the middle layer of the lamina is very dense, sharply de- 
fined from the intermediate layer and the latter layer composed of large cells with 
thin walls. By these marks it is plainly distinguished from ZL. digitata (L. jlevicaulis 
Le Jou.). On the other side it differs decidedly from L. Clustoni by no cork layer 
1) J. G. AGarpu supposes that the Laminaria from the west coast of Greenland mentioned by Brown in FI. 
Dise. under the name of L. digitata is to be referred to the present species or to L. atrofulva. Cp. J. G. 
Aa. Grénl. Lam. och Fue. p. 18. 
