86 POLYSIPHONIA. 



** Frond partially inarticulate ; the articulations of the stem and branches 

 obsolete, or indistinct, the surface-cells being small and irregularly shaped. 



10. P. elongata, Huds. ; stems robust, cartilaginous, irre- 

 gularly branched, beset, especially towards the tips, with 

 slender, tufted, multifid ramuli, which are attenuated at base; 

 joints about as long as broad, those of the stem reticulated 

 with veins. Harv. in Hook. Br. FL ii. p. 333 ; Wyatt. Alg. 

 Danm. No. 40. Conf. elongata, E. Sot. t. 2429. 0. denu- 

 data ; filaments nearly opaque, distorted, beset with wart-like 

 excrescences and bare of ramuli. Ceramium brachygonium, 

 Lyngb. Hyd. Dan. t. 36. y. sanguinolenta ; ramuli forming 

 broad, dense tufts, of a fine crimson, mostly at the tips of the 

 branches. Ag. Sp.Alg.\\.p. 85. P. rosea, Grev.! Fl.Edin. 

 p. 310. 



In the sea, on stones, shells, corallines, &c. Biennial. Spring. 0. and 

 y. are perhaps rather states of the plant than distinct varieties. Stems 6 

 12 inches high, as thick as whip-cord, tapering to the base and apex, ir- 

 regularly branched ; the branches erect or spreading, producing the first 

 season but few ramuli. In the winter these ramuli fall off, leaving the 

 branches bare, and the tips broken : but early in spring, broad tufts of 

 crimson, multifid ramuli, 1 or 2 inches or more in length^ issue from the 

 tips and upper part of the branches, and on these the fruit is borne. Cera- 

 midia ovate, sessile, either in clusters or scattered ; granules either imbedded 

 in the ramuli, or borne in minute, pod-like processes of the branches. Stems 

 scarcely adhering to paper ; ramuli very flaccid, and closely adhering. 



11. P. Gremllii, Harv. ; stems inarticulate, marked with 

 broken tubes, thick, cartilaginous, irregularly branched ; 

 branches subdivided, rather bare below, above densely 

 clothed with long, irregularly dichotomous, very slender, 

 pencilled, crimson ramuli ; axils acute; articulations of the 

 ramuli 3 6 times longer than broad, two-tubed. P. Lyng- 

 byati, Harv. in Hook. Br. FL ii. p. 328 ; (not Hutchinsia 

 Lyngbycei of AgardhJ. 



Shores of Bute, on the larger Algae, Dr. Greville. Frond 6 10 inches 

 high; stem as thick as that of P. elongata, cartilaginous, inarticulate, 

 marked with short, flexuons veins, and wholly destitute of joints. Branches 

 irregular, patent, sparingly divided, their lower part almost bare, the upper 

 densely clothed with long, very slender, crimson ramuli, which spread in 

 broad pencils, are much branched, straight, irregularly dichotomous, not 

 in the least attenuated at base, their axils very acute ; articulations marked 

 with two striae, rosy under the microscope, 2 4 6 times longer than broad ; 

 dissepiments pellucid. 



12. P. violacea, Ag. ; brownish-red or purple; stem in- 

 articulate, marked with irregularly-broken tubes, rather robust, 

 alternately branched ; branches quadrillions, several times 



