KONGL. SV. VET. AKADEMIENS HANDLINGAR. BAND. 20. N:0 5. 87 



differ, however, from it by being more robust, by the branches being very scanty in 

 general and especially more regularly feathered, and by most of the branchlets pre- 

 senting the appearance characteristic of the typical C. officinalis. From this, f. fiexilis 

 distinguishes itself by the greater slenderness and flexibility of all its parts, and by its 

 irregular and profuse branching, in consequence of which the upper branches form 

 dense bundles. At least upwards, in their upper portions, the branches are cylindrical, 

 terminating not seldom in a kidney-shaped fastening-disc, that is convex on the upper 

 side, plane on the under-side, and the upper cortical cells of which are isodiametrical, 

 the lower ones parallelopipedical, arranged in rows radiating like a fan. On the coast 

 of Bohuslan I have seen no form identical with this, although the plant is here very 

 variable in appearance. It often grows here in such localities where on the coast of 

 Norway I have found /. flexilis. In such a case, it often assumes an aspect differing 

 from the typical one, becoming stunted, and irregularly but at the same time scantily 

 branched. It accords with C. elongata Ellis in point of slenderness, but differs from 

 it by its branching and by the joints being chiefly round. On the other hand, it ap- 

 pears identical with that form of C. officinalis which Ruprecht in Alg. Och. p. 354 

 reports from the coasts of Russian Lapland and of Cisuralian Samoyede-land, possibly 

 also with the dwarfish form, richly and finely branched, observed by Magnus at Gle- 

 svser near Bergen (Magnus Nordseef., p. 70). 



The form for which I have proposed the name of robusta, is in most respects 

 the opposite of the preceding one. It differs from this as well as from the typical 

 form by being larger in size and especially more robust and by having more irregular 

 and scanty branches. The joints are round, cylindrical or slightly tun-shaped. The 

 main axes and the secondary axes of the first order, those with branches as well as those 

 without branches, are thickest at the middle, tapering towards the top as well as to- 

 wards the base, but more strongly towards the base. The branches of the last order 

 are, on the contrary, of equal thickness, and do not taper strongly towards the base, 

 as in the typical C. officinalis. The color is more vividly rosy red than that of the 

 principal form, and in preservation remains longer than in this. I have not found any 

 reproductive organs. 



Perhaps this plant is more rightly to be regarded as a northern species of the 

 genus. But as I know it myself but incompletely, and as such great authorities as 

 Areschoug (J. E. Ag. Spec. Alg. II p. 563) and Harvey (Phyc. Brit. t. 222) state that 

 C. officinalis occurs in a number of different forms, it is possible that that one which I have 

 called /. robusta, not having found it recognizably described in the literature, is only 

 a form of the common Scandinavian species of Corallina. I have not seen it on the 

 coasts of Sweden. 



Habitat. The species occurs, fastened to stones, rocks, or, more rarely, to algte, 

 as species of Laminaria, most commonly in rock-pools in the litoral zone or at low- 

 water mark, sometimes in 1—2 fathoms water, seldom at a greater depth. Ii grows 

 generally scattered, or in small close groups, and prefers sheltered places. Of the form 

 gracilis I have found specimens with tetrasporangia at the end of August. 



