THE MAKixi: AL(;.i: or m:\v England. l;jl 



tripartite, clustered in iiivolucrate ^vllorls at the nodes or on llic iinicr 

 side of short fascicled branches; cystocarps (favelhv) involucrate. 



A boautiful ponns, coniprisinj; liotwcrn ;>0 and 40 sprcirs, but only n'lirost'ntcd on 

 our Eastorn coast by a sin^lo species aud on the Western coast by two (loubtlully 

 determined species. The «jenus is distinguished from CalUthammon by the involucrate 

 favellic and by the disposition of the tetraspores. As we have Spermoihamuion sepa- 

 rated from Callithamnion in consequence of the absence of the gelatinous envelope 

 found in true favelhe, so we have Bornctia separated in a similar way from Grijfithvia. 

 The genus can generally be recognized at sight by the rather large but very delicate 

 cylindrical, oval, or, at times, globose cells, which do not bear immersion in fresh 

 water even for a short time, and by the branching, which is dichotonious or a modifi- 

 cation of the dichotonious typ«\ The accurate specific determination from sterile speci- 

 mens alone is generally impossible, so great is the resemblance of the fronds in the 

 different species. The antheridia vary very much in the dilVerent species. In our 

 only species they are sessile on the upper half of the globose terminal cells ; in G. coral- 

 Uiia they surround the nodes in tufts ; and in G. sctacea they are in dense ajjproxiraate 

 whorls, attached to the inner side of incurved branchlets. The tetraspores also vary 

 in the different species. In G. Bornetiaua and G. corallina they are in whorls at the 

 no<les, and are attached to the inner side of short simple branches, which form a whorl 

 around the noile. In G. setacea the tetraspores occupy a position which corresponds to 

 that of the antheridia. The favelliB are always truly involucrate and, as far as itj 

 known, terminal, in our species occupying the place of a suppressed dichotomy. The 

 development of the procarj) of C. corallina has been fully studied by Janczewski. In 

 that species he found two trichogynes to each carpogenic system, as is also the case in 

 the genus Ceramium. A non-sexual mode of propagation, by means of tells which 

 give oft' root-like processes, has been described by Janczewski in G. corallina, and a 

 similar process takes place in G. Bornetiana. 



G. Bornetiana, Farlow. {G, corallina f Ilarv., Ker. Am. Bor., Part 

 II, p. 228, non Agardh.— G. glohulifera, Kiitz., Tab. Phyc, Vol. XII, 

 PI. 30. — G. glohiferaj J. Ag. in part. — G. Bornetiana^ Proc. Am. Acad., 

 1877.) 



Kxs. — Alg. Am. Bor., Farlow, Anderson & Eaton, No. 88. 



l">onds dioecious and dimorphous. 



^^ALE PLANT. — Globoscly tufted, one to three inches high; filaments 

 itpcatedly dichotonious: lower cells cylindrical-obovoid, several times 

 longer than broad, becoming shorter and broader above; terminal cells 

 globose-pyriform ; antheridia sessile, densely covering the upper half of 

 terminal cell. PL X, Fig. 4. 



Fkmalk PLANT. — Two to fivc iuclios high, loosely tufted, filaments re- 

 peatedly dichotonious; lower cells cylindrical obovoid, becoming broadly 

 pyriform above and then gradually diminishing in size toward the tip; 

 favellii' solitary on the upper part of the superior cells; cells of involucre 

 10-20, unicellular, club-shaped, somewhat incurved. PI. XI, Fig. 3. 



Tetraspokic plant. — More slender than the female i)lant ; tetra- 

 spores tripartite, densely clustered around the nodes of special branchesj 

 cells of iuTolucre short and suberect. PI. X, Fig. 6. 



On wharves, sponges, shells, and occasionally on Zostcra, 



