INDEX 



Parthenogenesis, 6, 20 



Payne, 65 



Pellaea atropurpurea, 158, 184-6; and Figs. 191-3 



Phegopteris, 82-3, 87, 158, 161, 183-4, 286. 



See also under Dryopteris Phegopteris 

 Photography, xi, xii, 298-g 

 Phyllitis, 122. See also Scolopendrium 

 Phylloglossum, 22 

 Phylogeny, Pteridophyta, 23 ; and Fig. g 



ferns, 24, 89; and Figs. 10, 74 



Horsetails, 209 



Osinundaceae, 276 

 Polyploidy 



chromosome pairing in, 7-g, 35-8 



definition, 5 



frequency in Cruciferae, 13 



in apogamous ferns, ch. 11 



in British ferns, 282, Table 9 



in European Floras, 281-2, Table 8 



in Madeira ferns, 282-3, Table 9 



in Osmunda, ch. 3 



in Psilotum, 238-40 



production of, 22, 26, 28, 282-4 



summary, 285-7, 291 

 Polypodiaceae, 24, 128 

 Polypodium, chap. 8; 281, 283, 285-7, 291 

 P. virginianum, 138-40; and Figs. 141, 142 

 P. vulgare, ch. 8; and Figs. 126-44 



hexaploid, 134; aW Figs. 127-31, 134, 135^ 



pentaploid, i '^6; and Figs. I'^^d, 137, 138 



tetraploid, 132; aW Figs. 130-2, 135c, 136 



triploid, 136; andFigs. 135A, 139 



var. occidentale, 138-9, 141; and/ Figs. 140, 143-4 



var. semilacerum, Fig. 123a 



var. serratum, 132-4; aW Figs. 130, 131, 133, 135 

 Polystichum, 80, 88-93, 15 1-7 

 P. aculeatum, 88-92, 151-7, 286; and Figs. 77, 



796, 80, 156, 157 

 P. aculeatum X P . angulare, 154-7; andFigs. 160-2 

 P. angulare {P. setiferum), 89-92, 154-6; and Figs. 76, 



79« 

 P.falcinellum, 283 

 P. illyricum { = P. LonchitisxP. aculeatum), 150-4, 



285; andFigs. 155-9 

 P. Lonchitis, 88-92, 151-4; and Figs. 75, 78, 79c, 



156, 157 



P. setiferum, 89. See also under P. angulare 



Praeger, 61, 72-3, 224-5, 228 



Prophase, definition and stages, 33-4 



Prothallus 



apogamous prothalli, 20, 22, 57-8, 83, 158, 196; 



and Figs. 7, 42, 43 

 definition of, 17-19 

 in Equisetum, 19; and Fig. 6 

 in Isoetes hystrix, 258-9; and Fig. 257 

 in Ophioglossum, 264-8; and Figs. 264-6 

 in Osmunda, 26-9, 40; and Figs. 15-17, 26 



in Psilotum, 235-7; ^"^ Figs. 231-3 



in the Male Fern complex, 57; and Fig. 42 



saprophytic prothalli, 17, 235-7 

 Pseudofertilization, 159 

 Psilophytales, 16-17 



Psilotales, 16-17, 22-3; ch. 14; 285, 288 

 Psilotum, 22, 233-40, 285 



polyploidy in, 238-40, 285 



spiral structure, 240, 286 



tripolar spindle, 238 



vascular prothalli, 235-7, 243 

 P.Jlaccidum, 235, 239-41; and Figs. 230, 236, 237 

 P. nudum, 235-41 ; and Figs. 229, 231-5 

 P. triquetrum. See P. nudum 

 Pteridium aquilinum, 124-5; and Fig. i2^d 

 Pteridophyta, aim of the enquiry, 13, 16, 25 



characters of, 16-20 



enumeration of, 16-24 



phylogeny, 23-4 

 Pteris cretica, 22, 158, 161, 168, 17 1-7, 285; and 



Figs. 169c, 172-8 

 Pteropsida. See Filicales 



Quadrivalents, in Osmunda, 34, 36-8; andFigs. 20f. 



'22d, 24 

 Quillwort. See Isoetes 



Ramenta, 46-7, 49, 54, 75 

 Raphanohrassica, 13 

 Restitution nucleus, 165-6 

 Rosa, 5 

 Rosenberg, 5 

 Royal Fern. See Osmunda 

 Rumex, 5 



Runmaro, 104, 147 

 Russia, 14, 120, 140 



Saltation, 170, 288 



Saprophytic prothalli, 17, 236, 264-8; and Figs. 



231-3^ 264-6 

 Scolopendrium { — Phyllitis), 122-4, i42-7> 204-7 

 S. hemionitis, 143, 145-6; a W Figs. 147, 149-51 

 S. hybridum, 142-6, 157; andFigs. 145, 146, 148 

 S. vulgare, 123-4, H3, '45-7; andFigs. 123^, 124, 



148c 

 induced apogamy in, 204-7; and Figs. 208-10 

 Scotland, 48, 69, 93, 95-8, no, 112, 118, 246; 



andFigs. 83-6, 1076, 119 

 Segmental interchange, 53 

 Selaginella, 17, 22-3, 259-61, 273, 287-9; and 



Figs. 258-60 

 Shaw, 10 



Silhouettes, technique, 299 



Sledge. See Athyriumjlexile and Lycopodium annotinum 

 Sorus, use of in classification, 108 



parallel evolution, 291 

 Spain, 7, 125 



315 



