318 
Mycologia 
Oidium, 95 ; album, 34, 36 
Omphalia flavida. 264 
Onoclea sensibilis, 26—28 
Opuntia, 56, 59 
Origin of the volva aperture in Cryp- 
toporus volvatus (Peck) Hubbard, 
217 
Osmorrhiza, 256 
Osmunda Claytoniana, 26, 28 ; regalis, 
26, 28 
Otidea, 274 ; aurantia, 274 
Ovularia Syringae, 72, 73 
Oxygraphis cymbalaria, 256 
Oxypolis Fendleri, 256 
Oxyria digyna, 256 
Ozomelis stenopetala, 256 
Pachylophus caespitosus, 256 ; margi- 
natus, 256 ; montanus, 246 
Panaeolus, 185 ; papillionaceus, 185 ; 
retirugis, 185 
Panax, 56 
Panicum Crus-galli, 256 
Pannaria Mariana isideoidea, 261 ; 
pannosa, 261 ; rubiginosa, 261 
Parasitism in Hymenochaete agglu- 
tinans, 279 
Parnassia fimbriata, 256 
Parrya platycarpa, 249, 256 
Pectiantia pentandra, 256 
Penicillium, 21 1, 213 
Penicillium, Conidium production in, 
21 1 
Pentstemon confertus caeruleo-pur- 
pureus, 250, 256 ; procerus, 250, 256 
Peridermium, 109-114, 117, 122, 123, 
125—128, 137, 138; acicolum, 109, 
112, 114, 117, 118, 121, 137, 138; 
Betheli, 126, 138; californicum, 
114, 118, 137, 138; carneum, 112, 
114, 122, 123, 137, 138; cerebrum, 
109, no, 112, 113, 124, 133, 136- 
138; Comptoniae, 112, 124, 131, 
137, 138; deformans, 133, 138; deli- 
catulum, 1 12, 1 14, 1 16, 137, 138; 
elatinum, 242; Engelmanni, no; 
filamentosum, 109, no, 112, 123- 
126, 137, 138; Fischeri, no, 114, 
116, 137, 138; fusiforme, no, 112, 
1 13, 134. I3S. 138; giganteum, 133, 
138; globosum, no, 134, 136, 138; 
gracile, 114, 119— 121, 137, 138; 
guatemalense, 114, 121, 137, 138; 
Harknessii, 27, 109, no, 133, 138; 
inconspicuum, 112, 114, 115, 137, 
138; intermedium, 114, 120, 137, 
138; mexicanum, no, 134, 136; 
138; montanum, 114, 117, 118, 137, 
138; oblongisporium, no, 138; ob- 
longisporium Ravenelii, 122, 138; 
orientale, 109; pyriforme, no, 112, 
123, 126-128, 131, 132, 137, 138; 
Ravenelii, 122, 138; Rostrupi, no, 
112, 114, 120, 137, 138; stalacti- 
forme, no, 112, 124-126, 138; 
Strobi, no, 123, 129, 130, 137, 138, 
150 
Peridermium on pine, North Ameri- 
can species of, 109 
Peronoplasmopara Humuli, 194 
Peronospora, 79, 193, 196, 197, 200- 
203, 205-208, 210; alta, 205; an- 
dina, 203; Arenariae, 196, 197; 
Arenariae macrospora, 196 ; Ar- 
thuri, 207; Borreriae, 193; Botrytis, 
198; Cactorum, 80; Chamaesycis, 
204, 210; Chenopodii, 200, 202; 
Chrysosplenii, 210; conglomerata, 
194; crispula, 198; Cyparissiae, 
203; Cyperi, 192; Dentariae, 198; 
destructor, 196; Dianthi, 196, 197; 
effusa, 200—202 ; effusa major, 200— 
202; effusa minor, 195, 200—202; 
epiphylla, 202; Erodii, 194; Eu- 
phorbiae, 203 ; farinosa, 201, 202 ; 
Fragariae, 206, 207 ; Hyoscyami, 
208; Lepidii, 198, 199, 210; 
macrospora, 196; megasperma, 195; 
minima, 209, 210; Nicotianae, 
208; Niessleana, 197— 199; ochro- 
leuca, 198; parasitica, 197-199; 
parasitica Lepidii, 198; parasitica 
Niessleana, 198; Pepli, 202; Phlo- 
gina, 206 ; Phyteumatis, 197, 209 ; 
Plantaginis, 205 ; Potentillae, 206, 
207; Rubi, 207; Saxifragae, 210; 
Schachtii, 199; Schleideni, 196; 
Schleideniana, 196; Sempervivi, 70; 
Silenes, 197; sordida, 208, 209; 
sparsa, 206, 207; Spinaciae, 201, 
202; trichomata, 57, 208; Trifolio- 
rum, 205 ; violacea, 209 ; Violae, 
i95 
Peronosporales, Studies in North 
American — V. A review of the 
genus Phytophthora, 54 ; VI. Notes 
on miscellaneous species, 192 
Petradoria pumila, 256 
Peucedanum graveolens, 256; sim- 
plex, 256 
Peziza aurantia, 104, 274; auriflava, 
12; bicucullata, 276; coccinea, 274; 
Constellatio, 18; Crouani, 8, 104; 
echinosperma, 12, 13; exasperata, 
23 ; gemma, 18 ; globifera, 23 ; leio- 
carpa, 21; lobata, 22; modesta, 12, 
13 ; nigrans, 20 ; Persoonii, 22 ; poly- 
trichii, 23 ; radiculata, 275 ; reti- 
derma, 273, 277; rutilans, 276; 
sanguinaria, 16; scabrosa, 19, 20; 
splendens, 275 ; trachycarpa, 19 ; 
Wrightii, 15 
Phacelia, alpina, 256 ; heterophylla, 
256 
