Ser. Ciilouospur.uk 1. Fain. Siphonacece. 



Plate XXVI. 



CAULERPA CACTOIDES, Ag. 



Gen. Char. Frond consisting of prostrate surculi rooting from their lower 

 surface, and throwing up erect branches (or secondary fronds) of 

 various shapes. Substance horny-membranous, destitute of calca- 

 reous matter. Structure unicellular, the cell (frond) continuous, 

 strengthened internally by a spongy network of anastomosing fila-. 

 ments, and filled with semi-fluid, grumous matter. Fructification 

 unknown. — Caulerpa (Lamoibr.), from /cavXos, astern, and kpirco, to 

 creep. 



From ex surculis prostratis hie illic radicantibus et ramis erectis polymorplds 

 formata. Substantia corneo-membranacea. Structura unicellulosa, cellulce 

 membrand continud hyalind iutus filis cartilagineis tenuissimis anastomo- 

 santibus Jirmata et endochromate demo viridi repleta. Fruct. ignota. 



Caulerpa cactoides ; surculus robust, glabrous; fronds erect, shortly 

 stipitate, linear, distichously pinnate; rachis articulato-constricted ; 

 pinnae opposite, obovoid, saccate, about thrice as long as their 

 greatest width. 



C. cactoides ; surculo crasso glaberrimo, fronde erecta breve stipitata lineari 

 distiche pinnata ; rachide articulato-constricta v. nodosa ; pinnis oppositis 

 obovoideis saccatis diametro subtriplo longioribus obtusissimis. 



Caulerpa cactoides, Ag. Sp. Jig. v. 1. p. 439 ; Ag. Syst.p. 182. Sond. in 



Linn. v. 25. p. 661, et v. 26. p. 501. 

 Caulerpa corynephora, Mont. Voy. Pol. Sud, p. 15. t. G.f. 2; Mont. Sylloge, 



p. 452. Kiltz. Sp. Alg. p. 496. Harv. Alg. Austr. Exsic. n. 556. 



Chauvinia cactoides, Kiltz. Sp. Alg. p. 499. 

 Ahnfeldtia cactoides, Trevis. Linn. v. 22. p. 142. 

 Ahnfeldtia corynephora, Trev. I.e. p. 143. 

 Fucus cactoides, Turn. Hist. t. 171. 

 IIab. Rocks below low-water mark, and on the steep sides of deep rock- 

 pools. Western and southern coasts of Australia ; not unfrequent. 



Geogr. Distr. As above. Ins. Toud, D'Urville. 



Descr. Surculi extensively creeping, 2-3 lines in diameter, naked, glabrous, 

 glossy when dry, but shrivelled, rooting at long intervals, aud throwing up 

 fronds at every one or two inches. Fronds 10-12 inches long or more, 

 simple or with one or two lateral branches, broadly linear in outline, 

 simply pinnate. The rachis or stem is bare of pinnae for a short distance 

 above the base ; thence upwards it is regularly set with opposite pinnae, and 



