THE GREEN ALGAE OF NORTH AMERICA 243 



Var. AEQUATORIALE forma HORTENSE Wittrock in Wittr. 

 and Nordst., Alg. Exsicc., No. 1017 ; Hirn, 1900, p. 145, PI. 

 XXI, fig. 109. Smaller than the type in all parts, oosporesless 

 completely filling the oogonium, sometimes globose-ellipsoid, 

 and then not nearly filling the oogonium. 



veg. cell, female, 24-33 M diam., 2-4 /4 diani. long. 



oog., 42-5 1 n " 63-88 M long. 



oos., 38-49 fj. " 48-72 A* " 



These measures are for forma hortense ; in the variety the 

 vegetative cells and oogonia are proportionately longer. Green- 

 laud. Ecuador. 



31. OE. MEXICANUM Wittrock, 1878, p. 138; Hirn, 1900, 

 p. 147, PI. XXII, fig. in; Tilden, Amer. Algae, No. 257. 

 Dioecious; oogonia single, slightly swollen, cylindric-obovi- 

 form, pore superior ; oospore of the same form as the oogo- 

 nium, filling or nearly filling it, membrane smooth ; male plant 

 a little more slender than the female ; antheridia to 8-celled ; 

 spermatozoids binate, division vertical. 



veg. cell, female, 34-41 M diam., i^-3/^ diam. long. 



veg. cell, male, 30-38 A 4 " 2-3 



oog., 53- 6 3 <" " 76-110 At long. 



oos., 51-60 /j. " 63-80 M " 



anth. cell, 28-35 /a " 7-17 fj. " 



Mass., So. Dakota, Mexico. 



Ne*arly related to Oe. grande, but with vegetative cells aver- 

 aging larger and considerably shorter, oogonia more nearly 

 cylindrical, and more completely filled by the oospore. 



MACRANDRIA, OPERCULATA, GLOBOSPORA. 



32. OE. PUNCTATO-STRIATUM De Bary, 1854, p. 47, PI. II, 

 figs. 15 and 16; Wolle, 1887, p. 91, PI. LXXXV, figs. 3-5; 

 Hirn, 1900, p. 152, PL XXIII, fig. 123; Rabenhorst, Algen, 

 Nos. 214, 2276. Diocecious ; oogonia single, depressed-globose, 

 operculate, division median ; oospore depressed-globose, not 

 quite filling the oogonium, membrane smooth ; male plant 

 slightly more slender than the female ; antheridia to lo-celled, 

 cells slightly swollen ; spermatozoid single ; membrane of the 

 vegetative cells and oogonia marked with spirally placed dot- 

 like pores ; basal cell depressed-globose or subhemispherical, 

 not elongate, membrane vertically plicate. 



