284 F - BORGESEN 



porus open above their mouth like upper end. When the thallus is seen from 

 above the gland cells are easily observable as clear bodies between the dark 

 cortical cells. They are uniformly scattered over the thallus, and contain a clear 

 mucilage. 



The tetrasporangia (Figs. 30, 31) are formed in large sori on the surface 

 of the thallus. The sporangia are elongate-ovoid, often slightly tapering toward 

 the base, and transversly divided by oblique, often somewhat curved walls into 

 four spores. The sporangia measure c. 40 X 17 [x. 



As the plant was preserved in alcohol, nothing is known about the colour 

 in a fresh stete. 



Neither cystocarps nor antheridia were found. 



According to the descriptions of SCHMITZ, HAUCK and De TONI and to 

 my observations on dried material, Rh. Squamariae bears considerable resemblance 

 to the new species in its anatomical structure. On the other hand, characters 

 like the irregular crust-shaped thallus, the (presumably) marginal growth etc. 

 remove Rh. pacifica from the Mediterranean species. The generic position of 

 the former remains uncertain as long as we have not seen a more complete 

 material, including sexual plants. 



Area of distribution: Endemic. 



Fam. Squamariaceae. 



By Mme. Dr. A. Weber van Bosse. 



Cruoriopsis Duf. 



C. de Zwaanii Web. v. B. 



Weber van Bosse, Liste des Algues du Siboga, Rhodophyceae, prem. partie 

 1921, p. 267. 



In all essential points the alga of Easter Island resembles Cr. de Zwaanii, 

 but I have seen only tetrasporic plants. It may be that plants bearing cystocarps 

 are different from Cr. de Zwaanii. 



Area of distribution: Island Nias, west coast of Sumatra, Easter Island. 



Ethelia W. v. B. 

 E. pacifica nov. spec. 



Thallo substrato affixo, ± 300 (X crasso, constante e mesothallo et peri- 

 thallo superiore et inferiore. Mesothallo constante e filamentis ramosis, flabelli- 

 formibus. Perithallo superiore constante e filamentis obliquis in parte basali, 

 terminatis in partem superiorem satis latam erectam. Perithallo inferiore solum 

 filamentis obliquis munito, quorum pluria exeunt in rhizoidea. 



Cellulis perithalli superioris ± 3—6 jx latis et 8 — 9 jx altis, cellulis perithalli 

 inferioris 5— 9 {jl latis et 18 ;j. altis. Organis fructificationis non visis. 



