— 12 — 
oceurrit), Conidia ellipsoidea v. ovoidea, apice papilla pro- 
minente munita. Oospors® ignotz. Hab. presertim ın Solano 
tuberoso, nec non in aliis speciebus Solani generumque affınium. 
2. P. nivea (Unger.) Mycelii tubi validi, spe torulosi. 
Haustoria numierosa, vesiculiformia, obovata. Stipites conidi- 
feri fascieulaüi, bumiles, in apicem desinentes aut simplicem 
subulatum,, aut semel bisve breviter bifurcatuf, rarissime tri- 
furcatum ; sub apice ramis 1-3-4 muniti, horizontaliter paten- 
tibus, semel, bis, terve bi- (rarius tri-) furcatis. Rami primi 
ordinis plerumqgue brevissimi. rarius elongati, ultimi e bası lata 
subulati, patentes, recli, raro subllexuosi. Conidia subgloboso- 
oyoidea, magnitudine valde in»qualia, apice papilla obtusissima 
vix prominente munila. — Üogonia irregularıter subglobosa, 
‚membrana hyalina v. pallide fuscescente rigidiuseula; oosporz 
majuscule, globoss®, episporio tenui pellucido pallide luteo-fusco 
levi v. subrugoso munit®. Hab. in Umbelliteris variıs. 
3. P. pusilla dBy. Mycelii tubi validi, s®pe varicosi 
et torulosi; haustoria numerosa, vesiculiforma, obovata. Sti- 
pites conidiferi numerosissimi, plerumque 10—20 in fascieulum 
coalili e stomatibus emergentes, singuli breves („};— 7%; millim. 
alti), summo apice semel bisve dichotomi, raro trichotomi, 
sepius pseudo-trichotomi, ramo primario-altero bifurco altero 
simplici. Rami omnes brevissimi („45— 71; millim. longi), erecto- 
patentes; secundarii rarissime iterum bifureati; ultimi sursum 
attenuali, conidiis delapsis truncali. Conidia ovoidea v. obo- 
voidea, valde inzequalia, quandoque gigantea (ad „I; millim. 
longa), apice papillata (aqua aflusa Peronosp. nivee more 
zoosporas gignenlia). Oogonia ignota. Hab. in foliis Geranü 
pratensis et silvatici. 
Sectio 1. — Plasmatopare. Conidia candida, apice 
papillata, germinando protoplasma integrum e papilla aperta 
emittentia, quod liberatum mutatur in cellulam globosam, tubum 
crassum arcuatum mox protrudentem. 
4. P. pygmaa Unger. Mycelii tubi erassi, ssepe constrieti 
et varicosi; haustoria minula, obovata v. pyriformia. Stipites 
econidiophori fascieulati (2—5 et plures), singuli sursum latiores 
apice aut in ramulos 2—4 simplices breves conidiferos divisi, 
aut breviter bis dicholomi, cweterum omnino simplices, aut sub 
apice diviso ramos 1—4 breves, horizontaliter patentes, semel, 
bis, terve dichotomos gerentes. Ramuli ultimi eylindrico-conici, 
conidiis delapsis subtruncali. — Conidia ovoidea v. ellipsoidea, 
variee magniludinis, apice late et obtuse papillata. Oospors 
globose, matur& oogonii membranam tenuem pallide luteo- 
fuscam pellucidam omnino fere explenies, episporio tenui 
diaphano pallide luteo-fusco levi v. subrugoso, endosporio erasso 
nitido munit®. 
