116 L. KoLDERLP Rosenvinge. 



specimen, collected Aug. 15"\ has а sorus at the base of the old 



lamina, and a new sorus is developing in the lower part of the new 



lamina, but in the other plants collected in Julj'^ and August a new 



sorus was yet not visible Ч 



The muciparous canals are particularly well-developed in this 



species; they form a network which is easily visible with the naked 



eye in dried specimens and in specimens preserved in alcohol; they 



become particularly conspicuous after staining with methylen-blue^. 



Loc. Renskæret, 2—4 meters; along Cape Bismarck Peninsula; east side 

 of Koldewey Island; Danmarks Havn; Baadskæret. 



Fam. Chordaceœ. 

 Chorda (Stackh.) 



27. Ch. tomentosa Lyngb. 



K. Rosenvinge (1893) p. 854. 



In a gathering preserved in alcohol two small specimens of a 

 Chorda were found, intermingled among other algæ. They were 

 certainly sterile and feebly developed, but the hairs containing 

 numerous chromatophores showed them to belong to Ch. tomentosa. 

 They were about 5 cm. long and had not yet begun to develop the 

 outer, fertile layer. 



Loc. Bay off Vesterdalen in a deptli of at most 4 meters, Aug. 28th. 



Fam. Desmarestiaceœ. 

 Desmarestia Lamx. 



28. D. aculeata (L.) Lamx. 



K. Rosenvinge (18У8) p. 857, (1898 I) p. 59; Jonsson (1904) p. 32. 



Found at several localities, but only abundant at one. One 

 specimen has the basal portion; in this the primary axis bears 

 below two pairs of opposite branches, while the branches otherwise 

 are always alternate. I have found the same in plants collected on 

 the shores of Denmark. Plants collected in the middle of July 



^ Jonsson found many specimens in Kruuse's collections from East Greenland, 

 the lamina of which was divided into four parts (in one plant into five) and 

 he takes it for granted that these sections or laminæ have developed in four 

 (five) consecutive years. The fact that some of these plants bear a sorus or 

 mark after an emptied sorus on the uppermost section onl}', while the three 

 younger segments do not yet show апл' trace of a sorus, (1. с p. 28, fig. 2), sug- 

 gests the question whether more than one section may not exceptionally be 

 formed in the same л'еаг. 



' While Areschoug (1883 p. 7i did not find muciparous canals in the lamina of 

 this species, Guignard (1892 p. 37) found them in all examined specimens, though 

 in some cases the}' were small and not easily visible. 



