126 CHORD ARIACE^.—Mesogloia. rv. 



this reason, among otliers, I prefer retaining Mesogloia Zoster ce, Aresch. and M. 

 Lovenii, J. Ag. in the same genus as M. virescens. 



1. Mesogloia vermicularis, Ag. ; frond clumsy ; branches irregularly pinnate, 

 thick, worm-like, lineari-fusiform ; ramuli copious, long, flexuous, resembling the 

 branches ; filaments of the periphery moniliform, clavate, with spheroidal cells. 

 J. Ag. Sp. Alg. vol. 1, p. 58. Kutz. Sp. Alg. p. 544. Harv. Phyc. Brit. if. 31. E. 

 Bot. t. 1818. 



Hab. On stones and Algse between tide-marks. Annual. Halifax, W. H. H. 

 (v. V.) 



Frond a foot or more in length, with a subsimple leading stem set with lateral 

 branches, which are either simple and naked, or furnished with secondary, worm-like 

 branchlets. The principal divisions are two or three lines in diameter, irregularly 

 swollen here and there, often contracted at the base, curved or flexuous, and taper 

 to a bluntish point. The filaments of the periphery are densely set, shorter than 

 the diameter of the branches, and rise from the inflated, colourless, external cells 

 of dichotomous intra-peripherial filaments, which branch off from the longitudinal 

 filaments composing the axis. The peripheric filaments are coloured, tufted, clavate, 

 and bear spores in the centre of the tuft. In old age the stem and branches become 

 hollow, and the substance less gelatinous. This takes place most frequently when 

 the plant grows in deep water, beyond the influence of the tide. The colour is a 

 brownish olive. 



I collected only a single specimen of this plant at Halifax. 



2. Mesogloia virescens, Carm. ; frond filiform, gelatinous ; branches long, 

 erecto-patent, slender, villous ; ramuli more or less numerous, very patent, short, 

 obtuse ; filaments of the periphery as long as the diameter of the axis, dense, 

 moniliform, with spheroidal cells rather longer than their breadth. J. Ag. Sp. Alg. 

 vol. 1, p. 56. Harv. Phyc. Brit. t. 81. Kutz. Sp. Alg. p. 545. (Tab. X. B.). 



Hab. On Zostera at Nahant, Massachussetts, Miss E. H. Brewer. On small 

 Algas at Sand Key, Florida, W. H. H. 



Frond in the American specimens already seen, which are not of full size, two 

 to three inches long, in full grown (European) specimens 8 — 12 inches or more, 

 slender, branched in a pinnated or irregular manner, usually with a leading undi- 

 vided stem, set with patent, lateral branches. Branches horizontal or widely 

 spreading, short, or more generally elongated, filiform, of nearly equal diameter 

 throughout, appearing villous to the naked eye from the length and projection of 

 the peripheric filaments. Secondary branches resembling the primary, but shorter, 

 increasing in number with the age of the specimen. The peripheric filaments are 



