2 



Later I hope to be able to describe living individuals of this 

 interesting form of a true pelagic Alga, and the locality where it 

 grows. It will be distributed in Hauck et Ri enter, Phykotheka 

 universalis. 



Ralfsia pusilla (Stromf.) nob. 



Stragularia pusilla Stromf. in Notarisia 1888, p. 382. 



The genus Stragularia constituted by S t r o m f e 1 1 (Isl. Algveg. 

 p. 49) differs from Ralfsia thereby, that the cell-rows of the thicke- 

 ning layer consist of straight, vertical filaments rising from a single 

 horizontal layer, while in Ralfsia the filaments are more or less 

 curved, and the sporangia forms indefinitely extended, finally con- 

 fluent sori. 



The first species described, Stragularia adhcerens Stromf 

 Isl. Algveg. p. 49, has proved to be identic with Ralfsia clavata 

 (Carm.) Cr. I lately found this species at Trondhjem growing 

 on woodwork in the litoral region, and it seems to be very rare 

 here, bearing sporangia in the middle of October. 1 ) It represents 

 an intermediate form between Ralfsia and Stragulai ia, however, 

 without doubt most nearly related to the former. Cp. Rke. Al- 

 genfl. westl. Ostsee, p. 48, and Atlas, p. 9, t. 5 — 6. 



I agree with Batters, Mar. Alg. Berwick-on-Tweed, p. 67 in 

 regarding Stragularia only as a subgenus of Ralfsia, but not refer- 

 ring R. clavata (and R. spongiocarpa ?) to the former, as the fila- 

 ments not seldom are curved and the sori, so far as known never 

 confluent. Cp. Rke. 1. c. 



The other species referred by Strom felt 1. c. to his genus 

 Stragularia, now the type of the named subgenus, the above 

 quoted Ralfsia (Stragularia) pusilla, was first found on the leaf 

 of Laminaria saccharina, forming small crusts scarcely visible to 

 the naked eye. 



I got a Ralfsia from F. S. Collins collected at Marblehead, 

 Mass. U. S. A. in April and provided with sporangia, which except 

 as to the mode of growth fully coincides with R. pusilla. It sur- 



l ) Ralfsia verrucosa (Aresch.) J. Ag. was at the same time found in the 

 neighbourhood forming extensive strata on woodwork and provided with 

 sporangia. 



