The specimens which I have referred to f. clavulata partly resemble those from the 

 Gulf of Siam and the Maldives mentioned above, e. g. the branches are more delicate and 

 often less developed than in typical specimens of this form (PI. II, fig. 9). Other specimens 

 resemble typical f. clavulata in habit and strncture, or they are in part somewhat coarser 

 (PI. II, fig. 5 — 8). As remarked in Lithoth. Adriat. Meer. this form runs into f. crassiuscula 

 without any proper limit. Cp. 1. c. pi. I, fig. 4 — 6 and 10 — 15. It apparently stands in alrnost 

 the same relation to f. pteridoides in the present collection, but cannot be elucidated till better 

 material is known. The conceptacles of sporangia resemble those in Adriatic specimens, and 

 as to the conceptacles of cystocarps, which are very scarce, I refer to my remarks above 

 under the Maldive form. 



In Lithoth. Adriat. Meer. I classified a delicate and sparingly branching form under the 

 name of f. soluta. Cp. 1. c. pi. I, fig. 18 — $j- I have 1. c. in detail compared it with stunted 

 forms of other species arising from external causes or certain local conditions. As observed 1. c, 

 this form perhaps represents a species being in evolution, and as yet too little differentiated 

 to be looked upon as independent. Judging from the material in hand, however, this doesn't 

 seem to be the case ; it seems to be a dwarf-form which has risen from local conditions. There 

 is no certain limit to be drawn between it and f. clavulata. As also observed 1. c, the form 

 certainly diverges a great deal from the typical L. fruticulosum. Still the divergency is but 

 little greater than, for instance, that of L. calcareum f. subsimplex from f. valida of the same 

 species, viewed apart from quite monstrous forms. 



In the collection in hand occur sorae specimens which stand in nearly the same relation 

 to f. clavulata as the Adriatic f. soluta mentioned. The)- have probably risen in the same way 

 as the latter, e. g. selfloosening or broken branches of delicate specimens continuing their 

 growth lying loose on the bottom. In habit these specimens, however, are less diverging from 

 a small or stunted f. clavulata than the majority of the Adriatic specimens of f. soluta. On 

 the other hand they are sometimes so near approaching to L. australe f. miuutula that the 

 line can hardly be drawn with certainty, the less so, because these forms in the collection in 

 hand are represented, without any exception, by sterile specimens. 



Occurrence: In the sense taken above the species appears to be commonly distributed 

 over a great part of the investigated area. However, trom most ot the stations occur only a 

 few specimens, and from some stations only one has been brought home ; the greatest number 

 havs been brought home from stat. 109 and 240. A considerable bank of Lithothamnia at 

 stat. 66, between the islands of Bahuluwang and Tambolungan, south of Saleyer, is mentioned 

 by M. Weber x ) and Madame A. YVeber 2 ). This bank is not unlikely, at least in part, built 

 up with the species in question. There occurs, however, but a solitary small specimen from this 

 place. The specimen is in the lower part composed of a conglomerate of tubes of worms, 

 Bryozoa and other animals together with dead and living calcareous algae. Among the latter 

 is Mastophora melobesioides \ covered partly with lower animals, partly Peyssonnelia sp. and the 



1) Siboga-Expeditie I. Max Weber. [ntroduction et Description de L'Expédition. p. 38. 



1) A. Weber-van Bosse. Études sur les Algues de I. 'Archipel Malaisien. — Annales du Jardin Botanique de Buitenzen-. 

 Ser. 2, Vul. II, Leide igoi, p. 131. 



