MARINE ALG^E OF NEW ENGLAND. 125 



branchlets, numerous, tripartite or polysporic; favellre terminal on 

 lateral branches, usually composed of several distinct lobes, furnished 

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

 below. 



On wharves and Fuel. 



New York, Harvey; New Haven, Professor Eaton; Newport; New 

 Bedford; Wood's Holl; Europe. 



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

 mark. The species is easily recognized, when in fruit, hy the polysporic tetraspores 

 and by the favellye, which are terminal, not lateral, as in the rest of our species, and 

 have a sort of involucre formed by the growth of accessory ramuli from the cells just 

 below the favellse. When sterile the species may be recognized by the regular, 

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

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

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

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

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

 rather to C. roseum. The present species is placed by Bornet in the genus Corynospora, 

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

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

 iiion, although in some respects it differs from the rest of the genus, and the young 

 stages of the cystocarps remind oue strongly of Spermothamnion. The fruit is, how- 

 ever, a true favella. 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 iu European 

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

 later it becomes coarse. Specimens collected as late as possihle 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. 23, Fig. 1, 

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

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

 mined from the description. 



Subgenus EUCALLITHAMNION. 



Fronds erect, cortications generally present ; autheridia in tufts, either 

 on the nodes or interuodes of the branclilets ; tetraspores tripartite ; fa- 

 vellos usually binate, lateral. 



Sect. I. Pennat^e. 



Growth monopodia!, fronds disticliously pinnate, pinna] alternate, corti- 

 cations rudimentary or ivanting. 



C. rosetjm, (Roth), Harvey. (ft roseum, Phyc. Brit., PI. 230. — Phle- 

 hothamnion roseum, Kiitz.) 



Fronds capillary, two to four inches high, filaments diffusely branched 

 below, .main branches slightly corticated, secondary branches long, 

 flexuous, disticliously pinnate, pinnee crowded at the ends of the branches, 

 long, spreading or slightly incurved ; autheridia in tufts on the nodes 

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

 vellse binate on the upper branches. 



