Tin: MARINE ALGiE OF NEW ENGLAND. 33 



O. LIMOSA, Kiitz., var. CHALYBEA, Tab. Pliyc, Vul. I, PI. U, V\'^. 3 j 

 Lc Jolis, Liste dos Aljjcues Marines. 



Filaments .008-9'"'" in diameter, tlexnons, apex obtuse, oscillations 

 marked, cells about half as lon;^^ as broad, i)uri)lish colored. 



Eastport, Maine; Europe. 



Formint; a slimy layer on pilos. Our spociiucns seem to ajjroo wrll with spcciinong 

 from C'lurUonrg. O. littoralh, Harv'., of Crouan's Alg. Fiuistcrc, No. 32o, is apparently 

 vtTV nt'ar to this, if not the same. 



O. SIBULIFORMIS, Uarv., Pliyc. Brit., PI. 2')i h. 



Filaments .OOG-7^""" in diameter, at the end tapering to an incurved 

 point, cells about one-third as long as broad, bluish green. 



Charles River, Cambridge ; Europe. 



O. srnTonrLOSA, (Breb.). {Phormidium .suhtoniJosumj Brcl)., in Kiitz. 

 Tab. lUiyc, Vol. I, PI. 49, Fig. 5.) 



Filaments .OOS-i*"", cells nearly cuboidal, with rounded angles, so 

 that the filament appears slightly crenate. 



Eastport, Maine; Wood's Hell, Mass.; Europe. 



To this species is doubtfully referred a form common on wharves at Eastport 

 and on the government wharf at Wood's HoU, where it forms slimy patches, mixed 

 with Sjurulitia, &c. The lilameuts of this species hear a decided resemblance to tho 

 trichomata of Microcokits chthonoplastcs, and it may perhaps bo a question whether 

 they are not really a stage of that species in which the trichomata have escaped from 

 tho enveloping sheath. Opposed to this view is the large quantity of filaments and 

 apparently an entire absence of empty sheaths. That tho trichomata of M. chthono- 

 plastes often escape from the sheath can easily be seen, but how long they remain free 

 and how rapidly they increase under such circumstances is uncertain. 



MICROCOLEUS, Desmaz. 



(From ftiKpoc, small, and Ko?.eo^, a sheath.) 



rilaments slowly oscillating, destitute of heterocysts, several united 

 m a single gelatinous sheath, which is either simple or branching. 



31. cnxiiONOPLASTES, Thurct. ( Oscillator ia ch thonojylastcs^ Lyngbye — 

 Chthonohlastm Lynfjhci^ Kiitz. — Microcoleioi anfjuijornus, Uarv., Phyc. 

 Brit., PI. 249; Kiitz., Tab. Phyc, Vol. I, PI. Tu. — Chthonohlastm angui- 

 form is, Rab., Flora Europ. Alg., Sect. II, p. 133.) PI. II, Fig. 3. 



Sheaths elongated, fusiform, being six or more times broader in tho 

 Lcnter than at the extremities, simple, several twisted together so as to 

 form a green stratum, filaments dark green, about .005""° in diameter, 

 intricately twisted together, three or four only at the extremity of tho 

 sheath, but very numerous at the center, where the sheath is frequently 

 niptured, allowing the filament»s to protrude; cells as long as broad, or 

 a little broiuler, terminal cell acutely pointed. 



