114 
DICT Y OT ACEiE. — Punctaria. 
iy. 
of many rows of elongated cells, disposed longitudinally and firmly united into a 
compact cellular substance. The innermost of these are very long, the outer pro- 
portionably shorter. All, except those that compose the outermost row or circle, 
are colourless, and nearly empty. 
1. Pictyosiphon foeniculaceus, Grey. ; frond setaceous, very much branched ; the 
branches capillary, decompound ; ramuli subulate, alternate or scattered, rarely 
opposite. — J. Ag. Sp. Alg. vol. 1 , p. 82. Kiitz. Sp. Alg. p. 485. Haw. Phyc. Brit, 
t. 326. 
Hab. In rock pools, between tide-marks on stones and the smaller Algae. Sea 
shores from New Brunswick to Long Island Sound. Prince Edward’s Island, Dr. 
Jeans. Halifax, W. H. H. Boston Bay, G. B. Emerson and Mrs. Asa Gray, Sfc., 
Rhode Island, Air. Geo. Hunt , Mr. Olney , Sfc. Arctic Coast, Mr. Seeman. (v. v.) 
Fronds from six inches to one or two feet long, about as thick, or sometimes twice 
as thick, as liog’s-bristle, much branched and bushy ; usually having an undivided 
stem, set with many lateral branches, which are furnished with one or two series of 
lesser branches, also lateral, and very unequally and irregularly placed. Primary 
branches as long as the leading stem, or longer, very numerous. The spores are 
plentifully scattered over the branches, and are usually solitary. Colour a greenish 
or a brownish olive. Substance membranous, soft, but not gelatinous, adhering to 
paper in drying. 
VIII. PUNCTARIA. Grev. 
Boot a small naked disc. Frond flat, ribless, membranaceous, undivided. Fruc- 
tification , minute, dot-like sori, scattered over the whole surface, and containing 
roundish, sessile spores , accompanied by a few short, club-shaped, jointed parane- 
mata. 
The species comprising this group have the leaf-like habit of the smaller Lami- 
naria?, such as F. Fascia ; or of the restricted genus Diva, in which, by the older 
botanists, they would all have been placed. From Laminarias they differ in being 
of a more reticulated structure, formed of larger cellules, and in the very different 
fructification ; and from the Ulvas in colour as well as structure. To the genus 
Asperococcus , which immediately follows in order, Punctaria is very closely related, 
and only to be distinguished by the flattened, not tubular frond. But in Asp. 
compressus we find a strictly intermediate form, nearly as flat as a Punctaria , but 
evidently composed of two separable membranes. 
