THE li.(>K\ OF M i.i; \sK \. J 1 



Cosmarium iiitidiiliim DeNot., Element. 12. L867 



Cells small, length and breadth nearly equal, constriction deep, sinoa oar 



row; basal angles of half-cells obtusely rounded, ends rounds truo 



membrane thin and smooth; cells 25 10x22 30 

 Thedford. PI. VIL, Fig. 13, a and b. 



Cosmarium meneghinii Breb, in Elalfs Brit. Desm. 96 1848. 



Includes ('. crenulatum NTaeg. Einzell. AJg. 1849. 



Cells 1 -V£ times as long as broad, sinus narrowly linear; half cells Bub 

 quadrate, base straight, apex flat, truncate, or slightly concave; membrane 



smooth or slightly punctate; diameter of cells 'Jo -11 ■/, l.-nglh J, 



Vab— angulosum (Breb.) Rabh. PL Eur. Alg. III., 1G3. 1868. 

 Half-cells quadrangular; angles obtuse; diameter 18 fi. 

 Thedford. PI. VIL, Fig. 12, a, b, c. 



Cosmarimii tinctnm Ralfs Brit. Desm. 95. is is. 



Cells slightly longer than broad. 10-14x8-12 /i, constriction outwardly enlarg 

 ing, isthmus broad; half-cells broadly oval; cell-membrane tinged with 

 yellow or brownish, smooth; zygospore quadrangular, smooth. 



Minden. PL VIL, Fig. 10, a, b, c. 



Sub-section 2.— Chloroplasts 2 in each half cell. 



Cosmarium conspersum Ralfs Brit. Desm. 101. 1843. 



Cells quadrangular, 50-73 // in diam., about '., Longer than broad, angles ob 

 tuse, constriction deep, sinus linear; membrane covered wit h large, obi use 

 pearly granules giving the margins a crenate appearance. 

 Thedford. PI. VIL, Fig. 1, a, b, c. 



Cosmarimii umlnlatnm Corda Adman, de Carlsb. 243, L835 



Cells about 1}{ times as long as wide, ends broadly rounded, margins ondu 



late, constriction deep, sinus slightly enlarging out ward-: half cells -••mi 

 orbicular, with about 9 crenae to each half-coll; zygospore spherical, with 

 long spines, 2-3 dentate at apex. 

 Thedford. PL VIL, Fig. 2, a, b. 



Cosmarium rectangulare Guunow in Rabh. PL Eur. Alg. III.. 166. 18 - 



Cosmarium gottlandicum Wittr. Om Gottlands o. Oelands Sotvatteusalg. 60 L872, 



Cells longer than broad, 37-45 p long, 32 :5G ft in diam., constriction Linear; 



half-cells in front view sub-hexagonal or reniform, apex truncate, side 



view obovate, end view sub-elliptical; empty cell membrane delicately 



punctate. 

 Minden. PI. VIL, Fig. 4, a, b, c. 



Section II.— Central part of cell somewhal ventrioose. 



Cosmarium subcrnintum Hantzsch in Rabh. PL Eur AJg. ill . L64. 18® 



Somewhat longer than broad, deeply constricted, Binus Linear, apices dis 



tinctly quadricrenate, sides of each half-oell with I 6 crenae, the margin 



with about 3 rows of granules, of ten with 5 or more granules on the 



swoUencentralportion.lateral view spherical; 23 30 i long, 20 26 tin diam. 



Lincoln. PL VIL, Fig. 8. 



