128 REPORT OF COMMISSIONER OF FISH AND FISHERIES. 



Fronds globosely tufted, one to three inches high, filaments very del- 

 icate, slightly corticated at base, main branches many times divided* 

 secondary branches long and flexuous, pinnate with numerous pinnately 

 compound branchlets; antheridia sessile in tufts at the nodes of the 

 branchlets ; tetraspores tripartite, sessile on the upper side of bran chlets ; 

 favelloe binate on the upper branches. 



Yar. unilaterale, Harv. 



Fronds small and very delicate, branches and branchlets often secund. 



Var. fastigiatum, Har^. 



Branches fastigiate, the lesser ones densely ramulose at the tips. 



Var. Waltersii, Harv. 



Upper, branches distichously compound -pinnate, branchlets patent. 



On Zostera and different algae. 



Common in Long Island Sound ; Gloucester, Mass. 



The forms which have been referred on 6*ur coast to C. hyssoideum and C. coryrn- 

 bosum are hopelessly confused. Although as described by algologists the two spe- 

 cies are sufficiently distinct, in practice it is difficult to say where one begins and 

 the other ends. According to the books, the ramification of the upper branches ia 

 dichotomous iu C. coryrnbosum, whereas it is always alternately pinnate in C. hyssoideum. 

 In some of the forms of the last-named species, however, the tips are corymbose and 

 the cells of the axis are short and zigzag to such a degree that the tips at least appear 

 to be dichotomous. Of the two species in question, C. coryrnbosum is the less delicate 

 aud gelatinous, and is not so decidedly rose colored as C. byssoideum,\mt, as far as our 

 present information goes, although in its typical form C. hyssoideum is not only com- 

 mon — apparently more common than in Europe — but also easily recognizable, its ex- 

 treme forms are not sufficiently well known. The Kiitzingian method would be to 

 split the species up into four or five new species. According to Crouan and Bornet, 

 this species has seirospores. 



C. corymbosum, (Engl. Bot.) Lyngb. (G. coryrnbosum, Phyc. Brit., PI. 

 272; Etudes Phycol., Pis. 32-35. — Pcecilothammion coryrnbosum, Nieg.) 



Fronds tufted, two to three inches high ; filaments very delicate, cor- 

 tications wanting except at base, main branches several times pinnately 

 or irregularly divided, secondary branches pinnate with dichotomously- 

 multifid, fastigiate branches which end in hyaline hairs ; tetraspores 

 tripartite sessile at the nodes of the branchlets, occupying the place of 

 an ultimate branchlet ; antheridia in tufts, sessile on the upper inter- 

 nodes ; favellae binate on the upper part of the branches. 



Var. secundatum, Harv. 



Lesser branches frequently secund, ultimate branchlets irregular, 

 scarcely corymbose. 



On Zostera. 



Halifax, Boston Bay, New London, Providence, Harvey. The var< 

 secundatum, Massachusetts Bay, Greenport, Harvey. 



