SPIROGYRA. 



[ 717 ] 



SPIRORBIS. 



with the zoospore-like bodies just described 

 (see PYTHIUM). 



The species of Spirogyra have been 

 greatly multiplied by authors. The pecu- 

 liar fold projecting from the septum appears 

 to us to depend upon age and activity of 

 growth ; and the length of the joints de- 

 pends greatly on the stage of growth, as 

 they continually divide into two equal parts. 



Spiral band single. 



S. tenuissima. Vegetating filaments 1-3000" 

 in diani. ; joints four or five times as long 

 as broad ; spiral band open ; spore oblong- 

 elliptical (Hassall, pi. 32. figs. 9, 10). 



S. longata. Filaments about 1-1000" in 

 diam. ; joints six or eight times as long ; 

 spiral lax, spores oblopg-elliptical (Hass. 

 pi. 31. fig. 394). 



S. injlata (S. gastroides, Kiitz.). Fila- 

 ments 1-1680" in diam. ; joints four or five 

 times as long ; turns of spiral about five ; 

 fertile cells ventricose ; spores oblong- 

 elliptical (Hass. pi. 32. figs. 6, 7). 



S. communis (fig. 668). Filaments 1-1440 

 to 1-2000" in diam. ; joints two or three 

 times as long ; turns of spiral four, broad ; 

 spores elliptical (Hass. pi. 28. figs. 5, 6). 



S. quinina (PI. 9. fig. 17). Filaments 

 1-600'' in diani. ; joints once and a half or 

 twice as long; turns of spiral broad and 

 dense ; spores elliptical (Hass. pi. 28. fig. 2). 

 Varies in the length of the joints, which are 

 sometimes twice to seven times as long. 



Spiral bands two. 



S. decimina. Filaments 1-720" in diam. ; 

 joints two to foui' times as long; spiral 

 bands lax, crossing so as to present the 

 appearance of the letter X (IHiss. pi. 23. 

 figs. 3, 4). 



S. elongata. Filaments 1-1320 to 1-1200" 

 in diam. ; joints ten times as long; bands 

 lax (Berkeley, Gkanings, 12, fig. 2). 



Spiral bands numerous. 



S. nitida (PI. 9. fig. 26). Filaments 

 1-360' ' in diam. ; joints twice or three times 

 as long ; bands four, dense, closely veiled ; 

 spores elliptical (Hass. pi. 22. figs. 1, 2). 



S. maxima. Filaments 1-200 to 1-300" 

 in diani.; joints equal, once and a half or 

 twice as long; bands lax; spores globular 

 (Haas. pis. 18, 19). 



S. bellis. Filaments 1-400" ; joints equal 

 or twice as long ; bands two or three, lax ; 

 spores rounded; var. 8, spirals condensed 

 (Hass. pi. 24). 



S. pellucida (PL 9. fig. 27). ^ Filaments 

 1-840" in diam. ; joints four or six times as 

 long ; bands lax and slender ; fertile cells 

 ventricose ; spores globose (Hass. pi. 25). 



& rimilaris. Filaments 1-2040" in diam. ; 

 joints three or four times as long; spiral 

 bands four, broad, dense (Hass. pi. 27). 



S. curvatum (Sirogonium stictitum and 

 breviarticulatum, Kiitz.). Filaments 1-720" 

 in diam. ; joints four or five times as long ; 

 bands three or four, slender ; conjugation 

 direct, without a cross branch, approaching 

 Mougeotia. (Hass. pi. 26. figs. 1, 2.) 



BIBL. Hassall, Alg. 135; Kiitzing, Sp. 

 Alg. 437, Tab. Phyc. v. ; Pringsh. Flora, 

 xxxv. 465, Ann. N. H. 2. xi. 210 ; Braun, 

 Verjilngung, Ray Soc. ; Vaucher, Conferves, 

 37 ; Agardh, Ann. Sc. Nat. 2. vi. 197 ; 

 Rabenh. Alg. iii. 232 ; Carter, Ann. N. H. 

 1880, vi. 207 ; Petit, Spirog. of Paris, 

 1881. 



SPIROLI'NA, Lamk. (SPIBULINA, Ehr.). 

 Restricted. The long, narrow, crozier- 

 like modifications of Peneroplis (P. (Sp.) 

 austriaca, PI. 23. fig. 12) come under this 

 title. Fossil and recent. 



BIBL. D'Orb. For. Foss. Vien. 137 ; Car- 

 penter, Phil. Tr. 1859, 10 ; Parker, Jones, 

 and Brady, Ann. N. H. 3. xv. 230. 



SPIROLOCULI'NA, D'Orb. A sub- 

 genus of Miliola, among the Porcellaneous 

 Foraminifera. 



Char. Shell regular, equilateral, com- 

 pressed, oblong, oval, or elongated ; cham- 

 bers concentric on two opposing faces, in the 

 same plane, not embracing, all apparent and 

 with simple cavities ; orifice single, situated 

 alternately at the two ends of the longitu- 

 dinal axis, simple or with a tooth, frequently 

 prolonged into a tube. 



% planalata (PI. 23. fig. 7). Many 

 species, recent and fossil. 



BIBL. D'Orb. Ann. Sc. Nat. vii. 298; 

 Williamson, Rec. For. 82 ; Carpenter, For. 

 77 ; Parker, Jones, and Brady, Ann. N. H. 

 4. viii. 248. 



SPIROM'ONAS, Perty. A genus of 

 Flagellate Infusoria. 



Char. Body leaf-like, compressed, rounded 

 at both ends, and rolled spirally ; with one 

 or two flagella. 



S. volithilis= Cyclidium distortum, Duj. 

 Kent describes other species. (Perty. 

 Lebensf. 171 : Kent, Inf. 297.) 



SPI'ROPLEC'TA, Ehr. See TEXTULABIA. 



SPIROR'BIS, Daudin, Lamk. A genus 

 of Annulata, order Setigera. 



The elegant little milk-white flat spiral 



