OF THE XAYICrLE^. 



929 



rutilans, rar. viride ', 3Ionne7na octo- 

 carpoides, Meueo-. Europe, England. 

 1-1200". 



S. Ehretihergii (K.). — Frond parasitic, 

 lubricous, tufted, green, branched; 

 branches crystal-hyaline, soft, obtuse at 

 the apex ; naviculae (in dried specimens) 

 inconspicuous, tender, arranged in obso- 

 lete series, oblong in one view, truncate 

 in the other, with rounded ends. KB. 

 p. 113, pi. 23. i.2. = Naunema DiUwynii, 

 E Inf. p. 235, pi. 20. f. 13. Eui'ope. 

 1-1320". ^ 



S. spadiceum (Grey.). — Filaments ca- 

 pillary, tufted, much branched, of a red- 

 dish oliye-green colour; ramuli much 

 diyaricated, idtimate ones patent; nayi- 

 culse linear-oblong, elongated. Grey, in 

 Hooker's Br. Fl. p. 412. Scotland. 

 Fronds often with a faint metallic lustre 

 when dry. Filaments yeiy slender, and 

 of nearly equal thickness throughout. 



S. Adriaticmn (Ag.). — Filaments finer 

 than a hair, elongated, subsimple, when 

 dried of an opaque oliye green ; na\"iciilae 

 narrow, lanceolate. AgCD. p.21. Venice. 



S. confertum (S.). — Frond filiform, 

 sparingly divided throughout ; nayiculae 

 exceedingly crowded ; yalyes shortl}^ lan- 

 ceolate, acute, with indistinct, marginal 

 eti-iaj. SD. ii. p. 75, pi. 57. f. 359. Aber- 

 deen. -0008" to -0011". 



S. lutescens (K.). — Tufted, when dry 

 of a reddish colour, glossy ; filaments 

 subsimple, capillary, coloured and empty 

 at base, hyaline and filled with nayi- 

 culfe at the apex ; nayiculse oblong-lan- 

 ceolate, obtuse. KB. p. 112. Europe. 

 1-1200". 



S.Jlavum (K.). — Frond tufted, lubri- 

 cous, yellow; filaments tenacious, cry- 

 stalline, achromatic, straight, fastigiate, 

 branched; branches attenuated at the 

 apex, erect ; nayiculee scattered or inter- 

 ruptedly aggTegate, oblong or linear, with 

 obtuse or truncate ends. KSA. p. 101. 

 France. Nayicidse rather broad. 



S. hdeum (K.). — Frond tufted, yeUow ; 

 filaments achromatic, capillary, subfra- 

 gile, nearly equal throughout ; nayiculEe 

 linear or acicular, inconspicuous, alter- 

 nately loosely and densely compacted. 

 KA. p. 102. "^France. 1-1080". 



S. soi'didum (II.). — Fronds minute, 

 tufted, parasitic, dull brownish-grey; 

 filaments subdichotomous, achromatic, 

 with equal branches; nayiculae slender, 

 truncate ; yalves lanceolate-linear, rather 

 obtuse. KB. p. 113, pi. 24. f. l.=iT/ow- 

 nema sordidum, Meneg. On Zostera. 

 Europe. 1-1440" to 1-1200". 



S. tenue (Ag.). — Filaments arachnoid, 

 irregidarly branched; naviculse elliptic, 

 disposed almost in a single series. KB. 

 p. 112, pi. 23. f. 2. = Monnema tenue, 

 Meneg. Adriatic Sea. When dried it 

 appears as a sidphur-green stain ; fila- 

 ments inconspicuous from their tenuity, 

 Ag. Professor Kiitzing refers Agardh's 

 species to his S, mucosiim, but we doubt 

 their identity. 



S. simplex (E., K.). — Frond subsoli- 

 tary; na\'icul93 smooth, oblong, with 

 rounded ends, in a simple series within 

 flexible filiform tubes. KA. p. 99. = 

 Naunema simplex, E Inf. p. 234, pi. 20. 

 f. 12 ; Monnema inconspicuum, Meneg. 

 p. 436 ? Adriatic Sea. 1-1150" to 1-570". 



S. Lenormandi (K.). — Parasitic, short, 

 subsimple, in vroolly tufts ; filaments 

 achromatic, for the most part with empty 

 apices ; na^-iculse quadrangular, arranged 

 in a simple series. KA. p. 99. = Mon- 

 nema Lenormandi, Meneg. France. 

 Allied to S. tenue, but with smaller 

 frustules, Meneg. 



S. tenuissimum (K.). — Filaments 

 crisped, subramose, hyaline, yery slen- 

 der, densely interwoyen into a compact, 

 bro^^^l mucous stratum; nayiculse yery 

 minute, linear, truncate, in obsolete 

 series. IvB. p. Ill, pi. 23. f. 111. 1-3. 

 — 3Ionnema tenuissimum, Meneg. Adri- 

 atic Sea. 



S. stn'olatum (K.). — Fronds tufted, 

 green, crisped, capillar}^, fastigiately 

 branched ; filaments transversely stri- 

 ated, nearly empty at the base, filled at 

 the apex, crystal-hyaline throughout ; 

 na\'iculse oblong, obtuse in the lateral, 

 truncate in the front view. j3 clavigerum, 

 branches irregular, covered with obovate 

 or clay ate ramuli. KB. p. 114, pi. 26. f. 2. 

 = Monnema striolatum, Meneg. Ger- 

 many and France. 



Genus MICEOMEGA (Ag., Kiitz.) ( = Scliizonema, Meneg.). — Frustules 

 naviculoid, arranged in two or more longitudinal series within a gelatinous, 

 filiform or setaceous frond, or contained within tubes united longitudinally 

 into a compound, often membranaceous frond. Micromega is distinguished 

 from Schizonema by its comj)ound frond. We believe that under one genus 

 have been comprised species belonging to two distinct types, which perhaps 

 ought to fonn two genera. 



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