MARINE ALG.E OF NEW ENGLAND. 125 



brauclilots, niimerous, tripartito or pol ysporic ; favella* tenniiial on 

 lateral braiiohes, usually composetl ot* several distinct lobe^, I'urnislied 

 with an involucre by the growth of a few incurved accessory branches 

 below. 



On wharves and Fiici. 



New York, Ifarvci/ ; New Haven, rrofcssor Eaton; Xew^iort ; New 

 Dedford ; Wood's lioll j Europe. 



Apparently rather a common species, especially on wharves and Fuci at low-water 

 mark. The species is easily recognized, when in fniit, by the polysporic tetraspores 

 and by the favelhe, which are terminal, not lateral, as in the rest of onr species, and 

 Imve a sort of involucre formed hy the growth of accessory ramuli from the cells just 

 below the favolhe. When sterile the species may be rocogniz»'d by the regular, 

 broadly pinnate tips, at the end of nearly naked l»ranches. We have found both poly- 

 spores and favelhe on American specimens ; and in spite of the fact that our plants are 

 always more slender than European forms of the species, there can be almost no doubt 

 that we have the true C. Borreri. Whether all the sterile forms referred by Ameri- 

 can botanists to C. Borreri are correctly determined is doubtful. Some perhaps belong 

 rather to C. roscum. The present species is placed by Bornet in the genus Corynosporaj 

 because of the terminal and involcurate favelhe and polysporic tetraspores. As 

 writera differ about the limits of Corynospora, we have kept the species in Callitham- 

 nion, although in some respects it ditlers from the rest of the genus, and the young 

 stages of the cystocarps remind one strongly of Sjjennothamnion. The fruit is, how- 

 ever, a true fiivella. The number of spores in the polyspores in American specimens 

 rarely exceeds 8 or 10, whereas Niegeli puts the number as high as 20-28 in European 

 specimens. As usually found in early summer, the species is small and delicate, but 

 later it becomes coarse. Specimens collected as late as possible in the autumn are to 

 be desired, and the number of spores in a polyspore should be ascertained more defi- 

 nitely. In Contributiones ad Algologiam et Fungologiam, p. 44, PI. 2.3, Fig. 1, 

 Reinsch describes and tigures a Callithamnion Lahradorense, which is said to have poly- 

 spores — whether a polysporic condition of C. floccosum or not can hardly be deter- 

 mined from the description. 



Subgenus EUCALLITHAMNION. 



Fronds erect, cortications generally j^resent ; antheridia in tufts, either 

 on the nodes or iuternodes of the branchlets ; tetraspores trii)artite ; fa- 

 vellte usually binate, lateral. 



Sect. I. Pennat^e. 



Growth monopodial^ fronds distlchoushj pinnate, pinncv alternate, corti- 

 cations rudimentary or wanting. 



C. EOSEUM, (Roth), Uarvey. (C. roscum, Phyc. Brit., PI. 230.— Phlc- 

 bothamnion roscum, Kiitz.) 



Fronds capillary, two to four inches hi p^h, fdaments diffusely branched 

 below, main branches slightly corticated, secondary branches long, 

 tlexuous, distichously pinnate, pinnai crowded at the ends of the branches, 

 long, spreading or slightly incurs'ed ; antheridia in tufts on the nodes 

 of the branchlets ; tetraspores tripartite, sessile on the branchlets ; fa- 

 vcUie binate on the upper branches. 



