284 
Oenothera Lamarckiana, 69; muri- 
cata, 231; pumila, 111, var. 
rectipilis, 110, 111. 
Onopordon Acanthium, 252. 
Onosmodium occidentale, 247. 
Ontario, Salvia sylvestris L. in 
County Peel, 39. 
Ophioglossum vulgatum, forma pseu- 
dopodum, 106. 
Opuntia vulgaris, 231. 
Orchidaceae, 56. 
Orchids found in the Region of As- 
quam Lake, 56; of the Asquam 
Region, Further Notes on the, 235; 
of the Region of Asquam Lake, 
Further Notes on the, 131. 
Orchis spectabilis, 131, 236. 
Orobus Miihlenbergii, 157. 
Oryzopsis pungens, 109. 
Osmorhiza longistylis, 
caulis, 245. 
Osmunda cicutaria, 214. 
Osteospermum Uvedalia, 47. 
Oxalis, 44; stricta, 41, 44, Abnormal 
flower Structure in, 41, var. viridi- 
flora, 41, 44. 
Oxybaphus hirsutus, 129; 
neus, 129. 
Oxypolis rigidior, 164. 
var. villi- 
nyctagi- 
Pallavicinia Flotowiana, 272. 
Panicum aculeatum, 108; agrostoides, 
95; albemarlense, 108; Com- 
monsianum, 108; longifolium, 108; 
oricola, 108; scoparioides, 108; 
spretum, 108; virgatum, 108, var. 
cubense, 108; xanthophysum, 108. 
Parnassia caroliniana, 33, 164. 
Parthenium Hysterophorus, 251. 
Parthenocissus quinquefolia, var. 
hirsuta, 230. 
Paspalum pubescens, 108. 
Pease, A. S., Is Aster tardiflorus a 
Hybrid? 88; Taraxacum cera- 
tophorum in New England, 111. 
Peck Testimonial Exhibit, Installa- 
tion of the, 236. 
Pedicularis canadensis, forma prae- 
clara, 248; flammea, 142. 
Pellaea atropurpurea, 68; 
67, 68. 
Pellia, 266; Fabroniana, 272; Neesi- 
ana, 266. 
Pennsylvania, Carex gynocrates in, 
110; Range of Tedi novae- 
angliae extended into, 96. 
Penthorum sedoides, 65, 217. 
gracilis, 
Rhodora 
[DECEMBER 
Peplis americana, 11, 12. 
Persicaria pennsylvanica, 71. 
Petalostemon foliosus, 64. 
Petasites vulgaris, 220. 
Phacelia linearis, 247. 
Phegopteris alpestris, 203. 
Philadelphus coronarius, 226; in- 
odorus, 226. 
Philotria angustifolia, 108. 
Phlox pilosa, 164, 247. 
Phragmites communis, 119, 164. 
Phyllitis, 171. 
Physocarpus opulifolius, 226. 
Picea mariana, 110. 
Picris echioides, 253. 
Pine, White, 67. 
Pinus Banksiana, 64; Larix, 22. 
Pipsissewa, 237. 
Pisum maritimum, 160. 
Plants found on Woolwaste at West- 
ford, Massachusetts, Some Further, 
132; in eastern Massachusetts in 
the Spring of 1917, The tardy 
Flowering of, 219; Notes on some 
rare New York State, 28, 48; of 
eastern North America, Some new 
or critical, 152; of northeastern 
North America, Two new mari- 
time, 76; Preliminary Lists of 
New England,— XXV, 217. 
Platanus Wrightii, 23. 
Pleuranthe olivacea, 268, 269. 
Pluchea camphorata, 250. 
Poa angustata, 120; annua, 219. 
Podostemaceae, 217. 
Podostemum ceratophyllum, 217, 
225. 
Pogonia, 32, 56; affinis, 127, 235; 
ophioglossoides, 31, 32, 56, 131; 
trianthophora, 31, 50, 57, 131; 
verticillata, 31, 50. 
Polanisia graveolens, 217, [218; 
trachysperma, 217, 218. 
Polemonium reptans, 247. 
Polygala Nuttallii, 230. 
Polygonum, 133; achoreum, 232; 
acre, 134, var. leptostachyum, 129; 
allocarpum, 234, 235; aviculare, 
232, 235, var. latifolium, 234; 
dumetorum, 129; erectum, 232- 
234; Fowleri, 232, 235; Hydro- 
piper, 133; hydropiperoides, var. 
strigosum, 129; lapathifolium, var. 
nodosum, 129; Seeifinent, 133, 
134; littorale, 233; minus, 133, 
134, var. subcontiguum, 134, var. 
subcontinuum, 134; mite, 133, 
* strictum, b.  pusillum, 134; 
