STAUROGENIA. 



[ 735 ] 



Alg. 437; Tab. Phyc. v. pis. 8 & 9; 

 Thwaitee, Ann. N. H. xvii. 262; Ralfs, 

 Desmid. p. 146 ; Braun, Verjiingung, Ray 

 Soc. 1853, 287. 



STAUUOGE'NIA, Kiitz. A genus of 

 Unicellular Algae. 



Char. Cubical, the cells arranged in 

 groups of 4, 8, and 16. Propagation by tran- 

 quil gonidia arising from repeated division 

 of the cell-substance. S. quadratum (PL 62. 

 tig. 21). In freshwater pools. 



BIBL. Rabenh. Alg. iii. 80. 



STAUROXETS, Ehr. A genus of Dia- 

 tomaceoe ; including Staurostigma and Stau- 

 roptera. 



Char. Frustules resembling those of Na- 

 vicula, but the median nodule expanded 

 into a transverse baud 01- stauros. 



Striae resembling those of Navidda, or 

 intermediate between those of Navicula and 

 Pi/tnularia; often in \isible by ordinary 

 illumination. 



The species or forms are numerous. 



S. phcenicenteron (PI. 15. fig. 43. Valves 

 lanceolate, gradually attenuated towards 

 the somewhat obtuse ends ; stauros reaching 

 the margins of the valves; strise faint. 

 Freshwater; common; length 1-170" 



S.pulcMla (PL 15. figs. 44,45). Valves | 

 oblong, ends obtuse; frustules in front 

 view broadly linear, constricted in the 

 middle, and rouuded-truncate at the ends ; 

 striae distinct ; stauros not reaching the 

 margins. Marine; length 1-70". 



BIBL. Ehreub. Ber. Berl. Ak. 1843; 

 Kiitz. Bacill 104, and Spec. Ala. 89: Ra- 

 benh. Alg. i. 244. 



STAUROSPER'MUM,Kutz.=SxAURO- 

 CARPUS, Hassall. 



STEARIC ACID. The crystals of this 

 fatty acid are represented in PL 11. fig. 16. 



STEGANOPOREL'LA,Sniitt. A gen us 

 of Polyzoa = Metnbranipora pt. (Hincks, 

 Polyzoa, 176.) 



STEMONI'TIS, Gled A genus of 

 Myxomycetes, consisting of little, somewhat 

 stamen-shaped plants, either separate or 

 fascicidated, growing on rotten wood, &c. 

 They appear at first in the form of a muci- 

 laginous tiocculent expansion (fig. 695), from 

 which the membranaceous peridia grow up 

 (fig. 696). Many of these remain abortive ; 

 others are raised upon stalks, ripen, and, on 

 the separation of the fugacious peridium, 

 display themselves somewhat in the form 

 of DIACH.E A,but with a bristle-like columella 

 and no remains of the peridium. The flat, 

 cylindrical or globose, reticulated capilli- 



STENOGRAMME. 



Fig. 695. 



Stemonitis ferruginea. 

 Mycelium overgrowing decaying pine-leaves. 



Fig. 696. 



Stemonitis ferruginea. 



Immature (fasciculate) peridia arising from the 

 mycelium. 



tium is penetrated partly or through its 

 whole length by a columella continuous 

 with the peduncle ; the spores are inter- 

 spersed in the reticulations of the capillitium. 

 Capillitium and spores mostly of blackish 

 colour. There are numerous British species ; 

 & fusca is common. See ENERTHENEMA 

 and DIACHJEA. 



BIBL. Berk. Br. Fl. ii. pt. 2. 317 ; Ann. 

 N. H. i. 257, vi. 431, 2. v. 366; Greville, 

 Crypt. Flor. pi. 170; Fries, Sum. Veg. 455 ; 

 Syst. Myc. iii. 156. 



STENHE'LIA, Boeck. A genus of Co- 

 pepodous Entomostraca. Two species, on 

 Laminaria and in dredgings. (Brady, Copep. 

 ii. 32.) 



STENOC'YBE, Nyl. A genus of para- 

 sitic Micro-lichens found on the thallus of 

 Thelotrema and Graphis Sphinctrina, 

 Leighton. (Lindsay, Q. Mic. Jn. 1869. 146.) 



STENOGRAM'ME, Harv. A genus of 

 Rhodymeniaceae (Florideous Algae), con- 

 taining one very rare British plant, S. in- 

 terrupta, characterized by stalked, flat, fan- 

 shaped fronds, more or less divided dicho- 

 tomously into riband-like lobes, 3-5" high, 

 of a clear pinky-red colour. It is com- 

 posed of a central layer of large globular 

 cells, with a kind of rind of small cells. 

 The conceptacles form a sort of sorus or dark 



