o4 
17. 
THE OF D OCONEACG EAE 
1G” Viecetativercell punctatesse 4.5 eee cna 84. Oe. minus 
163) Vegetativercell not punctaresassen eee aoe 88. Oc. bohemicum 
Porteous ...5.o 5a Oe eee 120. Oe. nebraskense 
Operculate sia.ces ces iiacc Oren Ieee eee Re IE ee cen ee ee 18 
18 Divisionjohooconitmmimnediangae mee eee 19 
18:, Divisioniol oogoniumistipramediant 5.) 7.602 oan nie 24 
1852) Division omoozonium aininamediansns-rri en ese oe nee eeee 26 
18. Division of oogonium superior.............. 156. O8c. rigidum 
185 {Divisioniok oogomilimysupreme: sneer eee eee eee 29 
Divisioniof oogonitimmarkowee sot eee Ee cee 20 
Divasionvolsooroniumwidensa peek caeioe cee SEU cee eee eee 21 
20. Oogonium 28-35 X 28-38u....... 17la. Oe. decipiens f. dissimile 
20. Oogonium 46-54 X 44-54u...................157. Oe. bengalense 
20°) Oogoniumrbs7—64 GAS 53 eee ee 158. O8¢. indicum ° 
Diameter. of oospore: 22-261 neso sec eeoe ee On  e eee 22 
Diameter of oospore 30-32u........... 160b. Oe. areschougi {. robustum 
Diameter of oospore 42-4807 — a=. 3. hee ee eer eee 23 
Wiametemot oospore4s—oamase aici 159. Oe. brasiliense 
22.) eyymanGdrOSpOrOUusic..stiss aa renee ee eee 160. Oc. areschougu 
22 idioandTrospOorouses.ssse7 aoe 160a. Oe. areschougit var. americanum 
Vegetative cell 14-19u in diameter................ 157. Oc. bengalense 
Vegetative cell 19-26u in diameter................ 161. Oc. confertum 
24. Diameter of oogonium 14-26yu............... 163. Oc. clavatum 
24> Diameter omooronium 27-4244. + eee eee eer 25 
24. Diameter of oogonium 50-55u............... 173. Oc. costatum 
24. Diameter of oogonium 58-65u............... 174. Oe. boreale 
Oogonium 19-25u in length............ 164a. Oc. oelandicum {. minus 
Ooronitumy 25-527 intlengtheses sn. eee ae 164. Oc. oelandicum 
Oogonitum 40-45, in) lengthier ee eee 165. Oc. megaporum 
26. Suffultory cell enlarged......... 167b. Oe. platygynum var. continuum 
265 Suttittory. cell notaenlarced: see eae oe eee ee eee 27 
Diameter ot -vegetativercell G-l0us 5. a-- oa. cea eee ee 28 
Diameter of vegetative cell 12-l5u................ 166. Oc. bahusiense 
28. Gynandrosporous only.......... 167c. Oe. platygynum var. novezelandie 
28. Idioandrosporous only.......... 167a. Oe. PEE obtusum 
28. Gynandrosporous and idioandrosporous......167. Oc. platygynum 
@osporetwall:smooth::.:.. “oe Sonen. steers ae ene ee 
Oospore wall longitudinally ribbed................194. Oe. michiganense 
302° Tidtoandrosporous: Uaiae oc serie eae tioee i eeeeee a ao Creer 
305% ‘Gymandrosporousss.cc.n ss fora ee eee 32 
Oovomumi4s=60 62> (4s. 345 ene eee 190. Oe. praticolum 
@oronium 66-18 72-90 ure eae eee ee eee 191. Oc. supremum 
32. Diameter of oogonium 36—-42u............... 192. Oe. wabashense 
o2. Diameter of oogontumirAl2—ooan. i aes tae ee nae ee 33 
32. Diameter of oogonium 55-58u...189a. Oe. obtruncatum var. completum 
Beng tiohoogonium~oG-beuee eee seeee eee ae 189. Qe. obtruncatum 
Length of oogonium 68-75u............ 189b. Oe. obtruncatumvar. ellipsoideum 
34. Vegetative cell 2-3u in diameter............ 203. Oe. fusus* 
34. Vegetative cell 4-6u in diameter............ 210. Oe. virceburgense* 
34. Vegetative cell 6-13u in diameter........... 211. Oc. spurium* 
Diameter of vegetative cell not more than 2u...... 197. Oe. angustissimum* 
Diameter of vecetative:cell' 2-602. soe er ee eee Eee Cee oer 3 
Diameter of vecetative cell766—=)G0=938n. 22-2) a eee ee 268 
36: “SWithoutidwartamales 27505 2. 1s ees sr eee ce eee en ere ne eee 37 
36. ° Wath dwart tnailesia os 74 aha eee Oe ete ee cee ae 186 
Oogonium ‘opening by a pores?.2: <2. ce face -= ae See ee eee Cee 38 
Oogonium opening bya did is: i-32h..)eee.s nc eed oe ee eee 139 
38: ‘Pore median. on Rae, Hee cre sine ions Sen ceca Pere Cree See tee 39 
38. Pore supramedian (rarely varying to superior).................... 51 
38.” Pore superior... si $ 04 sees eaten © eas ee ee eee ee 63 
*See footnote, page 53. 
{Some variations of Oe. varians may be sought here. 
