254 TUFTS COLLEGE STUDIES, VOL. II, No. 3 



211, PI. XXXV, fig. 216; Wittr. and Nordst., Alg. Exsicc., 

 No. 12. Dioecious, nannaudrous, gynandrosporous ; oogonia 

 single, rarely double, sexangular-ellipsoidal, having the great- 

 est width and the pore slightly above the middle ; oospore same 

 form as the oogonium, quite filling it, membrane smooth ; 

 suffultory cell not or slightly swollen ; androsporangia 1-3- 

 celled, dwarf males on suffultory cells, slightly curved ; stipe 

 sometimes 2-3-celled ; antheridium exterior, unicellular. 



veg. cell, 9-16 /j- diam., 3-7 diam. long. 



oog., . 29-33 M " 33-39 M long. 



COS., 27-31 fJ. " 31-36 M " 



andr. cell, 13-14 M " 10-14 M " 



nan. stipe, 7-9 M " 21-30 M " 



anth. cell, 6-7 M " 9-12 n " 



Pa. Europe. 



Var. MAJUS Wille, 1880, p. 68; Him, 1900, p. 212, PL 

 XXXV, fig. 217; P. B.-A., No. 522. Larger, oogonia most 

 swollen at the middle, pore median. 



veg. cell, 15-23 /i diam., 2-3 diam. long. 



oog., 36-42 /a " 41-45 /j. long. 



oos., 34-40 M " 39-43 /j. " 



andr. cell, 14-18 /i " 8-10 /u " 



nan. stipe, 7-9 /u " 18-30 M " 



anth. cell, 6-8 M " 6.5-10 M " 



Mass. Europe. 



The form of the oogonium easily distinguishes this from all 

 other species, American or foreign. 



54. OE. HYSTRIX Wittrock, 1870, p. 133 ; Wolle, 1887, p. 

 87, PI. LXXXIV, fig. 8; Him, 1900, p. 213, PI. XXXV, fig. 

 218. Dioecious, nannandrous, gyuandrosporous (or possibly 

 idioandrosporous) ; oogonia single, ellipsoid, pore median; 

 oospore ellipsoid, nearly filling the oogonium, covered with sub- 

 ulate spines ; suffultory cell little or not swollen ; androspor- 

 angia i-3-celled, terminal cell obtuse ; dwarf males slightly 

 curved, on the suffultory cell ; antheridium exterior, unicellular. 



veg. cell, 17-28 /JL diam., i%-4>2 diam. long. 



oog., 38-48 fj. " 45-65 n long. 



oos., 37-46 M " 43-55 n " 



andr. cell, 17-18 /x " 13-18 /u " 



nan. stipe, 10-11 M " 22-25 M " 



anth. cell, 6-8 /x " 9-14 / " 



Pa. Europe. 



Distinguished from all other spinous species by the elongate 

 spines and the very short dwarf males. 



