122 MES. A. WEBEE-VAN BOSSE ON THE 



no. 8 are more slender, while the alga from Coetivy Reef is very much like specimens ii 

 Kiitzing's herbarium and named L. ohtusa yar. racemosa. The specimens from Egmon 

 Heef are rather short, but they probably represent young plants. They show the charac 

 teristic branching of the species, and all the branches have blunt truncated apices. 



3. Latjeencia papillosa (Forsk.), Grev., f. a^sthalica, in herb. Kiitzing. 



Aldabra, reef; dry specimen. 



Seychelles, Long Island ; dry specimen. 



Distribution. New Caledonia. 



I have been in doubt about these alg^e for they differ from typical specimens of 

 L. papillosa. They come near to two barren specimens from New Caledonia in 

 Kiitzing's Herbarium. Mr. Stanley Gardiner's specimens being also barren, I abstained 



from giving a diagnosis. 



4. Latjeencia spinulipeea, Kiitz. 



Kiitzing, Tab. Phyc. Bd. xv. 1865, tab. 61, p. 22. 



Chagos Archipelago, Diego Garcia ; in alcohol. 



JDistrihutioti. Indian Ocean. 



The specimens come near to some forms of L. ohtusa, but they are distinguished by 

 their small size. I think that until all the forms of L. ohtusa from the East Indies are 

 better known, we may retain Kiitzing's species. 



5. Latjeencia ptgm^a, n. sp. (Plate 12, fig. 6.) 



Eronde tereti, filiformi, tenui, circa 1 cm. alta, pulvinatim csespitosa, intricata ; ramis 

 primariis decumbentibus, secundariis erectiusculis ; ramulis clavatis, truncatis. 

 Eamis primariis usque ad 250 ju crassis, ramis secundariis et ramulis tetrasporiferis 

 100-150 ju crassis. Cystocarpiis et antheridiis non visis. 



Chagos Archipelago, Diego Garcia, no indication of depth ; in alcohol. 



Laurencla pygmcea is distinguished by its size, which is indeed dwarf for a Laurencia. 

 It grows in tufts, and the alcohol material looks as if it had grown on stones or shells 

 and had been cat off with a knife. The thallus consists of decumbent branches — I have 

 seen no rhizoids — which give off suberect ascending ones ; these are branched irregularly. 

 Sometimes the ramuli are subopposite, sometimes subverticillate or even single. They 

 are always slender, and not particularly short as are the ramuli of L. ^gannosa, Ta^m. 

 From this plant, L. pygmma may also be known by its thalli, which, though intricate, 

 are easily teased oat under a pocket-lens, whereas in the case of L. pannosa this cannot 

 be done, according to Zanardini, without damaging the frond. The mode of branching 

 reminds me of L. ohtusa, but the thallus is very slender, the main branches having a 

 diameter of 200-250 ii and the side-branches and tetrasporiferous ramuli from 100-150 ^• 

 Characteristic for this small alga are the swollen light-reflecting lateral membranes of 

 the central cells. From L. indica, Hauck, it is easily known by its small size. 



