HOW TO KNOW THE FRESH-WATER ALGAE 



SICKLE - SHAPED, acutely 

 curved; cresecnt - shaped 

 but curved more sharply 

 than an arc of a circle. 

 Fig. 374 



Figure 374 



SIPHON; SIPHONOUS, a 



tube; a thallus without 



cross partitions. 

 Sirogonium 95 



sticticum 95 

 SKEIN, a web-like expanse; 



a thin membranous 



growth. 

 S'oth 13 _ nA 



Snow Algae 13, 14, 34, 84, 



129 

 Sorastrum 60 



americanum 60 



spinulosum 60 

 Species defined 3 

 Sphaerellopsis 34 



iluviatilis 34 

 Sphaerocystis 48 



Schroeteri 48 

 Sphaeroplea 1 03 



annulina 1 03 

 Sphaerozosma 89 



excavata 89 

 Sphagnum 15, 70, 90, 110, 



1 33 

 SPHERICAL, not quite sper- 



ical. 

 SPICULE, a scale or needle 



in the wall of cells or as 



a decoration on a cell 



wall. 



SPINDLE-SHAPED, see Fusi- 

 form. 



SPINE, a sharply - pointed 

 projection from the cell 

 wall. 



Spirogyra, 95, 116; also 3, 

 6, 72, 94, 101 

 aequinoctialis 95 

 elongata 6 

 rhizobrachiales 95 



Spirotaenia 72 

 condensate 72 



Spirulina 158; also 159 

 laxissima 1 58 

 princeps 1 58 

 subsalsa 1 58 



Spondylomorum 27 

 quaternarium 27 



Spondylosium 89 

 pulchrum 89 



Sponge 65 



SPORANGIUM, a cell (some- 

 times an unspecialized 

 vegetative cell) which 

 gives rise to spores; the 

 case which forms about 

 zygospores in the Zygne- 

 matales (Conjugales). 



Starch 7, 8, 1 1 



STARCH-TEST, See Iodine 

 Test 



STAR-SHAPED, see Stellate 

 Staurastrum 75, 76 

 cornutum 75 

 rotula 75 

 STELLATE, with radiating 

 projections from a com- 

 mon center; star-like. 

 Stephanodiscus 1 86 ; also 

 187 



niagaroe 1 86 

 Stephanoptera 35 



gracilis 35 

 Stephanosphaera 29 



pluvialis 29 

 Stichococcus 104 



bacillaris 1 04 

 Stigeoclonium 113, 123; al- 

 so 108, 112 

 flagelliferum 1 1 3 

 Stigonema 169 

 muscicola 1 69 

 oce//atum 169 

 turfaceum 1 69 

 Stinging Cells 23 

 STIPE. a stalk, usually 



slender. 

 Stipitococcus 1 34 

 urceolatus 1 34 

 vasiformis 1 34 

 Stone-wort 1, 21 

 STRATIFIED, with layers 

 Stylosphaeridium 67 



stipitatum 67 

 SUB-APICAL, slightly below 

 the apex or below the an- 

 terior end. 

 SUBCYLINDRICAL, a figure 

 which is elongate with 

 lateral margins that are 

 parallel for most of their 

 length. See Cylindrical. 

 SUBFLAGELLAR, located at 

 the base of or just below 

 the point of origin of 

 flagella. 

 SUBQUADRANGULAR, not 

 quite square or with four 

 rounded angles. 

 SUBSPHERICAL, not quite 



spherical. See Oblate. 

 SULCUS, groove or depres- 

 sion in cells of Dinoflagel- 

 latae. (See Peridinium, 

 Fig. 258) 

 Surirella 1 88 



splendida 1 88 

 SUTURE, a groove between 

 plates, as in some Dino- 

 flagellatae; a cleft-like 

 crack or line in the spore 

 wall as in some zygo- 

 spores. 

 Symploca 1 63 



muscorum 1 63 

 Synechococcus 1 83 -> 



aeruginosas 183 

 Synechocystis 1 78 



aquatilis 178 

 Synura 154; also 2 

 Adamsii 1 54 

 uvella 1 54 



TEGUMENT, a skin; a firm 



outer covering. 

 TEST, a shell or covering ex- 

 ternal to the cell itself. 

 See Lorica. 

 Tetmemorus 69 



laevis 69 

 Tetradesmus 59 

 Smithii 59 

 w/sconsinense 59 

 Tetradinium 1 49 

 javanicum 1 49 

 simplex 1 49 

 Jetraedron 87; also 6, 86, 

 149 



asymmetricum 87 

 limneticum 87 

 lobulatum var. crassum 87 

 regulare var. biiurcatum 



87 

 regulare var. granulatum 

 87 

 TETRAGONAL, with 4 angles 

 which are arranged in two 

 opposite pairs. 

 Tetragoniella 141 



gigas 1 4 1 

 TETRAHEDRON, see Tetra- 

 gonal 

 Tetrallantos 49, 59 



Lagerheimii 49 

 Tetrapedia 183 



Reinschiana 183 

 Tetraspora 38, 44, 45, 100; 

 also 39, 42, 156 

 cy lindrica 38 

 gelatinosa 38 

 Tetrasporaceae 1 28 

 Tetrasporales 64, 67, 82, 99 

 Tetrastrum 55; also 56 



heterocanthum 55 

 THALLUS, a plant body 

 which is not differentia- 

 ated into root, stem and 

 leaf organs; a frond; the 

 algal plant. 

 Thea 1 1 5 



THECA; THECATE, a firm 

 outer wall, a shell, some- 

 times with plates as in 

 the Dinoflagellatae. 

 Thorea 1 25 



ramossisima 1 25 

 Tolypella 20 



intricata 20 

 Tolypothrix 174 



distorta 174 

 TOW; TOW SAMPLE, collect- 

 ing with a plankton net 

 by drawing it through the 

 water. 

 Trachelomonas 24; also 22 



granulosa 24 

 Trachychloron 1 4 1 

 biconnicum 141 

 TRANSVERSE FURROW, a 

 groove extending lateral 

 around a cell as in the 

 Dinoflagellatae. Fig. 375 



Jabellaria 1 87 



fenestrata 1 87 

 Tea 115 



Figure 375 



209 



