166 EEPORT OF COMMISSIONER OF FISH AND FISHERIES. 



abandoned altogether. The habit of the species of the present genus is much like that 

 of Laureneia, but the polysiphouous character of the fronds is more evident, the sub- 

 stance more delicate, and the branchlets more distinctly club-shaped than in that 

 genus. As in Laureneia, the apices are all depressed, the growing point being sunk in 

 a hollow concavity, from which, as well as from the younger part of the fronds, project 

 numerous tufts of hyaline, dichotomous, monosiphonous filaments. 



0. dasyphila, Ag. (Laureneia dasyphila, Phyc. Brit., PL 152.) 



Fronds dioecious, four to eight inches high, broadly pyramidal in 

 outline, cylindrical, robust, densely branched, generally with a percur- 

 rent axis and alternate, spreading, pinnately decompound branches, ulti- 

 mate divisions short, club-shaped or top-shaped, very obtuse at apex 

 and much constricted at base ; cystocarps sessile on very short branch- 

 lets. 



Yar. sedifolia, Ag. (Chondria sedifolia, Ner. Am. Bor., Part II, 

 PI. 18 g.) 



Branches fasciculate, approximate, branchlets obovate-oblong. 



On rocks and stones at low-water mark, and on Zosiera. 



Common from New .York to Cape Cod; Europe. 



A rather coarse species which does not collapse when removed from the water, but 

 which glistens on account of the water held by the tufts of hyaline filaments at the 

 tips of the branches. The species is recognized by its coarseness and broadly pyra- 

 midal outline and by its club-shaped ultimate divisions. The variety has rather less 

 olttuse tips and is not uncornnion. In spite of its coarseness, the species quickly decays 

 in fresh water. 



C. tenuissima, Ag. (Laureneia tenuissima, Phyc. Brit., PI. 198. — 

 Chondria tenuissima, Ner. Am. Bor., Part II, PI. 18/; Eludes Phycol., 

 Pis. 43-48.) 



Fronds dioecious, four to eight inches high, narrowly pyramidal in 

 outline, cylindrical, slender, rather loosely branched, with a percurrent 

 axis and long, suberect, alternate, virgate, pinnately decompound 

 branches, ultimate branchlets narrowly fusiform, attenuated at both 

 extremities. 



Yar. Baileyana. (Laureneia Baileyana, Mont., Ann. Sci.Nat., Ser. 3, 

 Yol. II, p. 63.— Chondria Baileyana, Harv., Xer. Am. Bor., Yol. II, 

 PI. 18 a. — Chondria striolata, Farlow, List of Marine Algae.) 



Branches erect, subsimple, beset with slender curved branchlets, which 

 are much attenuated at base and blunt at the apex. 



On stones at low- water mark. 



Squam, Mass., and common in Long Island Sound; Europe. 



A variable species, distinguished from the last by its lighter yellowish -color, less 

 dense branching, and slender fusiform branchlets. The typical form is common with 

 us, but not so common as variety Baileyana, which was considered by Agardh to be 

 the same as C. striolata Ag. The species seems to us rather to be a form of C. tonuis- 



