486 INDEX. 
Potamogeton natans, Linn., 211, 220. 
obtusifolius, Mert, & Koch, 211, 220. 
pectinatus, Linn., 23, 211; mentioned, 
18, 19. 
perfoliatus, Linn., 911, 220. 
prelongus, Wulf., 911. 
pusillus, Zinn., 211, 220. 
Schweinfurthii, A. Benn., 93; men- 
tioned, 18. 
trichoides, Cham., 211. 
Potatoes, experiments on (Sutton), 446- 
451. 
Potentilla palustris, Scop., mentioned, 222. 
silvestris, Neck., 209, 214, 
Pre-Glacial Flora of Britain (Mr. & Mrs. 
Reid), 206. 
Preservation of fossil fruits and seeds, 208. 
Primitive Angiosperms, 60, cf. 35; peri- 
anth of, 49, 50. 
Primulacew from Ruwenzori, 967. 
Proangiospermex, 35, 60; a hypothetical 
group of extinct plants, 33. 
Pro-anthostrobilus, 37, 58, 75. 
Prothalli, male and female, 31. 
Ргофососсасе trom Tanganyika, 135, 196. 
Protococcoidere of Lake Nyasa, 90; from 
Tanganyika, 131, 191; of Victoria N yanza, 
91. 
Protococcus gigas, Kütz., 146. 
Prunella vulgaris, Linn., 210, 218. 
Prunus spinosa, Linn., 209. 
Pseuderanthemew, mentioned, 7. 
Pseudolarix, Gord., mentioned, 199. 
Fortunei, Mayr, distrib., 205, 205. 
Psophocarpus palustris, Desv., 247; men- 
tioned, 230. 
Pseudotsuga, Carr., ment'oned, 199, 
japonica, Hayata, distrib., 203, 
205. 
Psychotria, Linn., mentioned, 256. 
Pteridophytes, 32; alternation of genera- 
tions, 31; from Pahang, 333; hetero- 
sporous, 323 ; strobili of, 38. 
Pteridospermese, 30, 76 ; foliage, 35 ; fructi- 
fications, 67 ; leaves, 70; stems, 70. 
Pterocarya caucasica, C. 4. Mey., mentioned, 
22]. 
Ptyssiglottis, Hallier f., 6, 7,9, 10; corolla, 
8; leaves, 8. 
antsophylia, Hallier f., 17. 
Ptyssiglottis dispar, Hallier f., 16. 
Jrutescens, Hallier f., 16, 
hirsuta, Hallier f., 9, 10. 
lanceolata, Hallier f., 12. 
leptoneura, Hallier f., 13. 
picta, Hallier f., 7. 
procridifolia, Hallier f., 15. 
radicosa, Hallier f., 6, 7. 
Pycnophyllum, Remy, mentioned, 3. 
Pycnostachys Elliotii, 5. Moore *, 275; 
mentioned, 232. 
urticefolia, Baker, 275. 
Pycreus Mundtii, Nees, 18, 25. 
Pyrola, Tourn., in Mexico, 431 ftnote. 
Pyrus Aria, Lar., 209, 214, 
granulosa, Bertol., 306. 
Malus, Linn., 209. 
Quercus, Tourn., iu Mexico, 431 ftnote. 
Blumeana, Korth., mentioned, 367. 
Editha, Skan, 366. 
Harlandi, Hance, var. integrifolia, 
Dunn *, 366. 
Rassa, Miq., 322. 
Robur, Linn., 210. 
Skaniana, Dunn *, 366. 
thalassica, Mance, var. obtusiglans, 
Dunn *, 366, 
“ Ragged Jack " Kale, cross-fertilization of, 
947; mentioned, 338; pollination of, 
240. 
Ranales, double perianth, 50; primitive 
features, 49; theoretie starting-point of 
Dicotyledons, 39. 
Капипешасеге, fossil, 200; from Ruwen- 
zori, 241; presenting primitive features, 
45, 46. 
Ranunculus, Linn., mentioned, 207, 
acris, Linn., mentioned, 212, 222, 
aquatilis, Linn., 209, 211, 
bulbosus, Linn., mentioned, 212, 222, 
Ficaria, Linn., mentioned, 222, 
Flammula, Linn., 209, 211. 
Lingua, Linn., 209, 211. 
membranaceus, Fres., 242 ; mentioned, 
222, 231. 
nemorosus, DC, 209, 212; men- 
tioned, 222. 
