I^aviculacea.] infusokial animalcules. 493 



MiCEOMEGA parasitimm. — Slender, tufted, curvatc, parasitic, 

 gelatiuo-cartilaginous, of a pale yellow colour, sometimes brown; 

 very much branched, capillary ; series of naviculae dense ; navicular 

 in length 1-1 380th. Length of frond two inches. 



M. JJomhi/cinutn = Schizonema Agardhii (Ehr.) — Of a pale yellow 

 coloiu', contorted, implicate, curved, much branched, capiliaryj,- 

 naviculae remotely connected, indistinctly defined, and very minute. 

 Heligoland (See P. 4, fig. 208, and P. 17, figs. 43, 44, 45, 46.) 



M. patens. — Very small, parasitic, floccose-capillary, very fine, 

 gelatinous, branches divergent or patent, obtuse at the extremi - 

 ties ; series of naviculae and the secondary intei'nal tubules distinct, 

 but the naviculae very small; their length 1 -2400th. Length of 

 frond l-12th. 



M. flag elUfer urn. — Small, tufted, parasitic, floccose-capillary, 

 branches erect, divided into flagelliform fibres ; rows of naviculae 

 and internal tubules distinct. Length of naviculae l-1920th to 

 1-1 560th. Length of frond 1-1 2th to l-6th. 



M. Uneatum — Decumbent, densely tufted, capillary, olive.coloured, 

 elastic, glossy, subramose, branches tapering at the extremity, and 

 widely curved ; series of the lanceolate naviculae very distinct. 

 Length l-1320th to l-1200th. 



M. floccosum. — Minute, almost capillary, branched, rather delicate, 

 gelatinous ; rows of the obtuse and truncate navicuhe, and of the 

 secondary inner tubules, quite distinct. Length of naviculae 1 -720th. 

 Length of frond half an inch. 



* * Forms rigid and cartilaginous. 



M. hyalinum. — Colourless, hyaline, gelatinous, soft, setaceous 

 at the base, very branched, branches attenuate, capillary and free 

 at the apex ; rows of naviculae few and lax, interwoven with but 

 few fibres; minute naviculae, oblong- lanceolate, obtuse on the 

 secondary side, and truncate on the other. Length of navi- 

 culae l-960th to l-780th; of frond 1 inch. Trieste and Spalato. 

 Adriatic. 



M. tenellum. — Colourless, hyaline, gelatinous ; cartilaginous, seta- 

 ceous, branched, sub-dichotomous; branches at the extremity very 

 fine and void ; rows of the slender naviculae, and their tubules, dis- 

 tinct. Length of frond 1 inch. Spalato. 



