SCHIZOGONIUM. 



[ 567 ] 



SCHIZOTHRIX. 



Soc. Vol. 1853. p. 181. pi. 2); Kutzing, Sp. 

 Alg.p. 891. 



SCHIZOGONIUM, Kutz.— A genus of 

 Ulvaceae (Confervoid Algae), nearly related 

 to Prasiola, distinguished by filiform fronds, 

 which, when young, present only a single 

 row of cells, but subsequently, by collateral 

 subdivision, have two, four or eight parallel 

 rows. Of the species given by Kutzing, 

 the following appear to be British : 



1. 5. murale [Bangia velutina, Ktz., olim) 



Fig. 638. 



Schizogonium murale. 

 Filaments of frond in various stages of development. 

 Magnified 300 diametersiyx jju 



(fig. 638). Fronds of a single row of cells 

 1-2400 to 1-2160'' in diam., double 1-1440 

 to 1-1200", triple 1-720"^ cells half as long 

 as broad, dull green. On damp earth. 



2. S. percursum {Enteromorpha, Ag.). 

 Frond with a double row of cells 1-1200 to 

 1-900" in diam., length of cells equal to the 

 breadth, bright or pale green ; collapsed 

 when dry. Marine. 



3. <S. Icetevirens (Bangia, Harv.). Frond 

 with a simple row of cells, 1-1800 to 1-1440" 

 in diam., rigid, with a double row 1-600", 

 bright or yellowish green. Marine. 



^^ Bangia lacustris, Harv., is given as a 

 oubtful species. 



- BiBL. Kiitz., Sp.Alg. p. 350, Tab. PJiyc. 

 H: pis. 98, 99; Harvey, Brit. Alg. 1 ed. 

 p. 172, and Br. Marine Alg. p. 211. 



SCHIZOLOMA, Gaudichaud.— A genus 



of Lindsaeeae (Polypodaeous Ferns). Ex- 

 otic. 



SCHIZONEMA, Ag.— A genus of Diato- 

 macese. 



Char. Frustules short, resembling those 

 of Navicula, aggregated in longitudinal rows 

 in a filiform branched, slender and lax gela- 

 tinous tube (cajloma). Marine. 



Sporangia (spermatia, see Micromega) 

 external, simple, sessile upon the filaments. 



Kiitzing describes thirty-eight species, 

 three of which are doubtful. 



S. Dillwynii (PI. 14. fig. 12). Caelomata 

 hyaline, tufted, wavy, lubricous, bright green, 

 much branched; end branches short, nume- 

 rous, patent, attenuate and somewhat acute; 

 frustules towards the base of the frond 

 remote and scattered, towards the ends 

 crowded, oblong-truncate in front view ; 

 valves lanceolate 1-1020" in length. 



Compare Homceocladia, Micromega 

 and Rhaphidoglcea. 



BiBL. Kutzing, Bacill. p. Ill, and Sp. 

 Alg. p. 97. 



SCHIZOSIPHON, Kiitz.— A genus of 

 Oscillatoriacese (Confervoid Algse), contain- 

 ing CalotJirix scopulorum, fasciculatum, and 

 perhaps other species of Harvey's ' Manual.' 

 Another British species has also been de- 

 scribed by Caspary, S. Warrenice (PI. 4. 

 fig. 13). This last plant extends over large 

 surfaces of maritime rocks, in tufts of vari- 

 able size, from 1-4 to 1-2" in thickness, of dull 

 blackish-green colour. The erect filaments 

 are fastigiately branched (a), the basal cell 

 of the branches broader and hemispherical 

 (c) ; the ochreal sheaths are obscure [b), 

 frequently exhibiting a spii'al-fibrous struc- 

 ture in decay {d, e); the apices of the 

 branches are much attenuated. 



BiBL. Kiitz. Sp. Alg. p. 326, Tab. Phyc. 

 ii. pi. 47 et seq. ; Harvey, Brit. Mar. Alg. 

 p. 224 ; Caspaiy, Ann. Nat. Hist. ser. 2. 

 vi. p. 266. pi. 8. 



SCHIZOTHRIX, Kiitz.— A genus of Os- 

 cillatoriaceee (Confervoid Alga?), of which 

 two British species, growing over maritime 

 rocks, have been described. 



1. S. Creswellii (PL 4. fig. 17). Tufts 

 1-2 to 3-4" high, olive-coloured; filaments 

 cm-led, 1-3600" in diameter at the base, 

 1-12000" at the summit, in twisted bundles, 

 penicillately corymbose above. 



2. S. Smit}iii\Coleonema,1h.vf.). Stratum 

 dense, dirty red ; filaments closely entwined, 

 more or less laterally concreted, 1-9600 to 

 1-8400" in diameter; sheaths lax, multipli- 

 catc, the internal prolonged and exserted. 



