MARINE ALGAK FROM EASTER ISLAND 



299 



crecti, teretes, clavati, in inferiori parte ca. 1 mm lati, in superiori ca. 2 mm, 

 apice late rotundato, ant simplices, aut ramosi, ramulis clavatis, sparsis, paucis, 

 irregulariter exenntibus, interdum ramosis, ramellos in superiore parte gerentibus. 

 Tetrasporangia sparsa in suneriorc parte ramorum orta. 



To judge from the specimens collected the plant forms low dense tufts, 

 ca. 1 '/a -2 cm high, on rocks between tide 

 marks. 



The decumbent creeping filaments, about 

 1 — 1V2 mm thick, are fastened to the substra- 

 tum by means of short, thick, vigorous hapters 

 (Fig. 39 a). From these prostrate filaments 

 erect ones grow up. These measure at their 

 base about 1 mm in diam., gradually thickened 

 upwards, attaining twice their basal diameter 

 and slightly clavate. 



Of the erect filaments the more robust 

 ones are branched in their upper half. They 

 carry some few lateral branches, especially near 

 their upper end, where several may be clustered 

 together. The branches grow out to all sides 

 without any order, they are clavate like the 

 primary branch and sometimes carry sub- 

 terminal branchlets. 



Tetrasporic plants only were gathered. 

 The tetraspores are found in the cortical 

 layer, scattered over the surface, especially 

 in the upper end of the branches. 



As to the limitation of the species in this troublesome genus I refer to 

 my remarks in »The marine Algae of the D. W. I», vol. II, p. 244. I regret 

 that, in describing a new species, I add to the difficulties. Nevertheless I think 

 this is the best way to take until the very desirable revision of the whole 

 genus has been undertaken. 



The present plant surely comes near a group of species (f. i. L. perforata, 

 radicans, vag-a. decumbens etc., comp. KtJTZlNG, Tab. Phycol., vol. XV, pi. 49 — 5 1 ) 

 about which J. Agardh, in »Epicrisis», p. 649 says: »nec mihi patet quomodo 

 distinguantur». 



Area of distribution: Endemic. 



Fig. ». Laurencia claviformis now spec. 

 Parts of plants, a c. '1, b c. 5 /i. 



Chondria Ag. 



Subgenus Coelochondria Falkenb. 



Ch. repens no v. spec. — Figs. 40, 41. 



Thallus teres, minutus, ca. 1 — 2 mm altus et 200 — 400 a latus, in aliis algis 

 epiphyticus, partim e ramis repentibus, rhizoideis brevibus robustis adfixis, par- 

 tim e ramis curtis, erectis constructus. 



