The species betongs to the section Innatce. Overgrown con- 

 ceptacles of sporangia are numerous in the peripherical portions 

 of the specimen examined, some of them, however, filled with local 

 formations of tissue, which are again covered with a new thicke- 

 ning layer of the frond. The cystocarpic conceptacles quite likely, 

 at least now and then, also grow down into the frond, or are 

 filled with local formations, and the latter covered with a new 

 thickening layer of the frond. 



Remark on the synonomy. I quoted in Lithoth. p. 123 (151), 

 that the plant recorded by Ellis 1. c. from Falmouth and the Isle 

 of Man as „Corallium pumilum album, fere lapideum, ramosum" 

 on one hand somewhat reminds one of certain forms of L. tophi- 

 forme but on the other rather approaches the present species in 

 habit. It not unlikely is a form of the latter, although apparently 

 more branched. 



Belation to other species. This plant is quite different from 

 any other species that I know, perhaps most nearly allied with 

 L. flabellatum f. Oranii Fosl. Lithoth. p. 70 (98), from which, 

 however, it differs both in development and other essential cha- 

 racteristics. 



Habitat. The species has been tåken on a depth of about 

 7 fathom. Specimens collected in August are scantily provided 

 with reproductive organs. 



Occurrence. Hitherto with certainty only met with at Cumbrae 

 on the western coast of Scotland (Batters). 



Lithothamnion crassum Phil. 



in Wiegm. Arch. p. 388; Hauck, Meeresalg. p. 273. 



f. typica Fosl. 



Lithoth. p. 3 i (,59); Hauck 1. c. t. I, fig. 1, 3; tab. nostr. fig. 14. 



Remark on the species. Coll. Hariot No. 4. This plant 

 appears to be widely dispersed especially in southern waters. By 

 comparing the specimen fig. 14 with those delineated by Hauck 

 1. c. it will be seen, that they agree well with each other, and this 

 specimen, gathered on the coast of California, must be referred to 

 the typical form of the above species. I certainly have not found 



