266 
W. E. WADE 
This variety is about twice as large as the typical and bas trifid 
or cjuadrifid apices of the processes further subdivided. Cell 
length 7ô a, Cell width 75 -i, Istliinus 17 u. Sniall unnamed lake 
on road behveen the town of Paradise and Tahquainenon Falls, 
Chippewa County, Michigan. 
Personal communication Avith Mr. A. M. Scott reveals that 
lie bas found a similar organism in Florida, altbough bis spéci¬ 
mens are not as large as the Michigan specimens and are 
proportionately wider. 
S. brevispinum Bréb. Oakland County. 
5. brevispinum var. boldtii Lagerheim. Cheboygan County. 
S. brevispinum var. reiusiim (West and West) Borge. Barry 
County. 
5. clepsydra Nordst. fa. Oakland County spécimen are smaller than 
the tyjiical. 
S. connatum var. americanum West and West. Callioun County. 
S. controversum Bréb. Barry, Marquette and Schoolcraft Counties. 
S. corniitum fa. rediicliim fa. nov. (PI. 2, Fig. 6). 
Hic oryanismus a planta typica difjert possessione nnicae 
spinae brevis convergentis iitroque in margine laierali. Cellulae 
aliter forma ornamentatioque ut in planta typica. Celliila 32 \j. 
long., sine spinis 27 u. lut., ciim spiniis 33 jx lat., isthmiis 10.5 
lai. 
This organism difï'ers from the typical by the presence of a 
single short convergent spine on each latéral margin. Otherwise 
the cell shape and ornamentation agréé with the typical. Cell 
length 32 tx, cell width wilhout spines 27 jx, cell width with spines 
33 ;x. isthmus 10.5 ,a. Acid swamp along road north of Manistique 
Schoolcraft County, .Michigan (collected by G. W. Prescott). 
S. creniilatum var. briitaniciim Messikommer. Barry County. 
S. ciispidatum var. maximum var. nov. (PI. 2. Fig. 5). 
Haec varietas a specie algue ab eius aliis varietatihus differt in 
possessione spinaram valde elongatarum, angulis paiiluliim 
mammillatis, differt neenon cellula spinisqiie subeurvatis a ver- 
iiee visis. Cellula sine spinis 38 a long., 23 {x lat., ciim spinis 81 
lut., isthmus 5-6 y. lat., spinae 32 y. long. 
This variety differs from the typical and from other varieties 
of the typical by the possession of greatly elongated spines, the 
slightly mamillate angles, and the slightly ciirved cell'and by 
the spines in vertical view. Cell length without spines 38 jx, cell 
width without spines 23 jx, cell width with spines 81 u., isthmus 
5-6 îx, length of spines 32 ix. Otis Lake, Barry County, Michigan. 
S. dejectum var. inflafum West. Gogebic County. 
