SPH.EROPSIS. 



[ 707 ] 



SPHrEROZYGA, 



cell, and swim about as free biciliated zoo- 

 spores, of globidar or shortly cylindrical 

 form, from 1-2280 to 1-1680" long, either 

 bright red or particoloured red and green, 

 the point bearing the cilia, however, always 

 colourless. After a time they become 

 coated with a cellulose membrane, cease to 

 move, and grow into a spindle-shaped body, 

 the ends prolonged into hair-like points. 

 The growth appears to be always in the 

 middle, the hair-Uke points remaining ; 

 thus the spindle-shape is retained until the 

 length reaches 1-24' or more, and the first 

 septum appears in the middle of the filament, 



S. annulina (PI. 9. fig. 14) appears to be 

 the only well-known form. It is a rare 

 Conferva, growing on flooded fields ; it 

 does not seem to have been recorded in 

 Britain. 



For Sph. crispa and purictalis, see Ulo- 



THEIX. 



BiBL. Kiitz. Sp. Ah/. 362, & Tab. PJtyc. ; 

 Braun, T'erjiinc/unf/, Ray Soc. 1853, 165; 

 Cohu, Ber. Berlin. Ak. 1855 ; Ann. Sc.Nat. 

 4. v. 187 ; Ann. N. H. 2. viii. 81 ; CienkowsM, 

 Bot. Zeit. xiii. 777 ; Eabeuht. Ahj. iii. 318. 



SPH^^ROPSIS, Lev.— A genus of Sphse- 

 ronemei (Stylosporous Fungi), growing 

 upon stems, &c. ; apparently only stylospo- 

 rous forms of Sphseriaceous genera. 



BiBL. Fries, Sum. Veget. 419 ; Tulasne, 

 Ann. Sc. Xat. 4. v. 115. 



SPH.^ROP'TERIS, Wall.— A genus of 

 Dicksonieee (Polypodiaceous Ferns). 8. 

 harbata ; India. (Hooker, Syn. 49.) 



SPmEROSlRA, Ehr. See Vol vox. 



SPH^ROTHE'CA.— A genus of Sphjs- 

 liacei (Ascomycetous Fmigi), closely allied 

 to Erysiphe. S. pannosa is common on the 

 leaves and fruits of a rose ; S. Castaynei, on 

 the leaves of hops &c. (Cooke, Handb, 645 ; 

 Tulasne, Carp. i. 208.) 



SPH^EROT'ILUS.— A genus of Crypto- 

 coccese, consisting of cells an-anged in rows, 

 connected by mucus, forming a flocculent, 

 variouslj- divided floating layer. S. natayu 

 (PI. 3. fig. 21), brownish, in organic liquids : 

 said to purify the water. 



BiBL. Rabenht. Alg, ii. 8 ; Eyferth, Jn. 

 Mic. Soc. 1881, 97. 



SPH^ROZOS'MA, Corda.— A genus of 

 Desmidiacese. 



Char. Filamentous; filaments flat, fra- 

 gile, their component coUs closely united 

 by means of minute (glandular) processes, 

 and deeply divided on each side into two 

 seg'ments. 



S. vertebrattmi (PI. 14. fig. 9, front view ; 



fig. 10, side view). Cells about as long as 

 broad ; connecting processes oblique, one on 

 each side. Length of cell 1-1430". Not 

 uncommon in ditches. 



S. excavatum. Cells longer than broad ; 

 connecting processes sessile, two on each 

 side. Length of cell 1-2570". 



After separation, the cells conjugate ; spo- 

 rangia elliptical. Other species. 



BiBL. Ralfe, Br. Desmid, 65 ; Rabenht. 

 Aly. iii. 148. 



SPH.EROZO'UM.— A genus of Radio- 

 larian Rhizopoda. 



It consists of a spherical group of rounded 

 bodies consisting of sarcode with distinct 

 nuclei, surrounded by a zone of siliceous 

 spicules, the whole being imbedded in a com- 

 mon gelatinous matrix. The centre of the 

 mass is vacuolated; and the whole often 

 becomes a hoUow sphere. (Huxley, Comp, 

 Anaf. ; Carpenter, Microscope.') 



SPILEROZ'YGA, Agardh {Anabcena, 

 Bory, Brebisson). — A genus of Nostocha- 

 cese, difleriug from the allied genera only in 

 the sporaugial ceUs being separated by vesi- 

 cular cells. As the sporaugial cells are de- 

 veloped from the ordinary cells, and this 

 gi-adually, the vesicular cell will appear at 

 certain epochs to have a sporangial cell on 

 one side and an ordinary cell on the other ; 

 but this arises merely from the fact that 

 the sporangial cells are developed singly 

 and successively, first one on one side of 

 the vesicidar cell and then one on the other, 

 and so on, to whatever number of adjacent 

 sporangial cells there may be developed on 

 either side of the vesicular cell ; and those 

 nearest the latter will therefore always be 

 the largest, until the whole have acquired 

 tlie full size. Ralfs describes seven British 

 species. 



* Filaments moniliform; sporangia elonyated, 

 not turyid. 



S. Carmichaelii. Filaments with tapering 

 exti-emities ; ordinary joints distinct, sub- 

 quadrate ; sporaugial cells oblong ; vesicular 

 cells spherical. — Ralfs, Ann. N. H. 2. v. pi. 

 8. fig. 7 ; Harvev, P/ujc. Br. pi. 113 A ; Mar. 

 Alyce, 2. ed. pi. 27. fig. D. 



Belonia toridosa, Carmichael ; Sphcerozyga 

 compacta, Kxxiz. ; Anabcena marina, Brebis- 

 son ; Cylindrospernium Carmichaelii, Kiitz. 

 Sp. Aly. 294, Tab. Phye. i. pi. 99. 



Var. tenuissima, with very slender fila- 

 ments. Forming a tender, very thin stra- 

 tiun of a dark or bluish-gi-een colom*, on the 

 damp soil of salt-marshes flooded at spring 



2z 2 



