44 VALONIACE^. 



formed. Fig. 5. Portion of the capitular filament ; the latter figures more or less 

 magnified. 



II. PENICILLUS. Lamarck. 



Root fibrous, much branched, matted. Frond stipitate, dendroid. Stipes erect, 

 cylindrical or compressed, incrusted, -wholly composed of numerous longitudinal, 

 unicellular branching filaments woven together into a compact spongy mass ; and 

 crowned with a dense pencil of confervoid, articulate ramelli, whose branches are either 

 free, or cohere together in fan-shaped laminae, and are invested with a porous pellicle 

 of carbonate of lime. 



If Mer-men have beards and shave them, the Algae included in this genus may serve 

 as shaving brushes. The root is much branched and its fibres matted together, and 

 generally penetrates deeply into the sand in which the plant grows. The stipe is more 

 or less coated with carbonate of lime, and composed of a multitude of closely placed 

 and densely interwoven longitudinal, unicellular filaments, which send ofi" laterally, 

 throughout their length, short, fastigiate, corymbose ramelli, that unit« together to 

 form a periphery. Thus far we have a structure closely agreeing with that of a Codium. 

 But from the apex of this compact, spongy stipe there springs a dense tuft or capitulum, 

 composed of dichotomous, articulated, free filaments ; and the whole frond bears a 

 striking resemblance to a shaving brush. The habit is similar to that of Chamcedoris^ 

 from which the spongy, multicellular stipe distinguishes it ; and to Chlorodesmis, which 

 difiers in having a capitulum formed of unicellular filaments. 



The species naturally arrange themselves in two groups, or sub-genera, which Kiitzing 

 has separated ; a separation which is hardly needed, where the species are so few in 

 number and so closely related in structure. 



Sect. 1. Haligraphium, Endl. (Corallocephalus, Kiitz.) ; branches of the capitulum 

 free. 



1. Penicillus dumetosus^ Dne. ; stipes short, thick, somewhat compressed, velvetty; 

 filaments of the capitulum loosely spreading, ultra-setaceous, flaccid, deep-green ; their 

 joints cylindrical, many times as long as broad, equal, obtuse, strongly constricted at 

 the nodes. Dne. Cor. p. 97. Nescea dumetosa, Lamour. Polyp, p. 259. pi. S,fig. 3, 

 a. B. Corallocephalus dumetosus, Kiitz. Sp. Alg. p. 506. (Tab. XLIII. A.) 



Hab. Key "West and Sand Key, W.H.H. Soldier's Key, Prof. Tuomey. (v. v.) 



i?oo?, a dense mass of fibres deeply sinking in the sand. /Sfi^oes, 1-3 inches long, 

 half-inch to nearly an inch in thickness, sometimes rather hollow in the centre, more or 



