INDEX 



Equisetiim {cont.) 



gametophytes, 19, 223; andY'ig. 6 

 geographical distribution, 210, 227 

 geological history, 23, 209 

 hybrids, 224-31 ; and Figs. 224-8 

 previous chromosome counts, 215 

 seasonal periodicity, 212-14 

 E. arvense, 210, 212, 214-15, 219-21, 225, 231; 



and Figs. 217-19 

 E. hiemale, 210, 212, 218, 230, 232; aW Figs. 215 a, 



216 

 E. limosum, 18, 210, 212, 215, 224-5, 228, 231; 



and Fig. 222 a and c 

 E. litorale, 212, 224-9, 231, 285; and Figs. 



224-7 

 E. maximum, 2 10, 2 1 2-15, 23 1 ; aWFigs. 2 12, 220, 22 1 

 E. Moorei, 229-32, 285; and Figs. 225, 2276 

 E. palustre, 18, 210, 212, 215, 232; an^ Fig. 222^ 

 E. pratense, 210, 212, 214-15, 231 

 E. ramosissimum, 210, 213, 218, 230, 232 

 E. robustum, 18, 211-12, 221, 232; and Figs. 213, 



2140. 217 i 

 E. scirpoides, 210, 212, 218; an</ Figs. 211, 215^ 

 E. sylvaticum, 210, 212, 214-18; and Fig. 6 

 E. trachyodon, 211-12. 218, 227-32, 285; and 



Figs. 225, 227, 228 

 E. variegatum, 210, 212, 218, 230-1; aW Figs. 213^, 



214A 

 Erophila, 13 

 Eusporangiatae, 262 



Farmer and Digby, 159, 187 

 Ferns. See Filicales 

 Fertilization, 17, 19 



in Equisetum, 19, 268; and Fig. 6 



in Ophioglossum, 268 

 Feulgen technique, xi, 221, 293, 295, 297 

 Filicales, 24, 284, 289 

 Finland, 120-1 



Fixation, 26, 152, 174, 215, 250; andY'ig. 173 

 Flowering Plants 



evolutionary mechanisms, 13-16, 290 



examples, ch. i 



frequency of polyploidy, 281-2 



life history, 16, 18 



summary of conclusions, 283-7 

 France, 7, 47, 100, 105, 108, 132, 145 



Gametophyte, definition, 18. See also under 



Prothallus 

 Gerassimowa, 14 

 Giant mother cells, 166, 168 

 Glaciation, 140-1, 283-4, 290. See also Ice Age 

 Goldschmidt, 4 



Greenland, 118, 121, 140; and Fig. wjb 

 Gregoire, 2 

 Guernsey, 255-7, 262-3; and Figs. 254/!', 261a 



Gymnocarpium, 85-7, 94 



G. Dryopteris (Oak Fern), Figs. 71-3 



G. Robertianum, Fig. 726 



Haploid, definition, 5 



Scolopendrium, 205-6; and Figs. 208-10 

 Heilbronn, 103 

 Heim, 197 

 Helminthoslachys, 262 

 Heterospory, 254-5, 291 

 Heterotype, 34 

 History of biology, 1-3 

 Holloway, 233, 235-6 

 Holly Fern. See Polystichum Lonchitis 

 Holttum, xii, 81, 124 

 Homotype, 34 

 Horsetails. See Equisetum 

 Hulten, 140, 147 

 Huxley, 65 

 Hybridization, methods, 48 



importance in evolution, 283 



summary, 285 

 Hybrids, sterility of, 51 



between apogamous and sexual species, 171 



in apogamous ferns, 194 



synthesized hybrids, 49-53, 154-6, 191 



wild hybrids, Asplenium, 100-6; Dryopteris, 

 59-61, 70-5, 1 9 1-3; Equisetum, 224-31; Lyco- 

 podium, 251-2; Woodsia, 147-51 

 Hydropterideae, 17 



Hymenophyllaceae, 24, 262, 270-3, 280 

 Hymenophyllum, 262, 270, 272-4, 280, 286-7 

 H. tunbridgense, 272-4; and Figs. 273-5 



spiral structure, 273-4; '^"^ ^ig. 275 

 H. unilaterale, 272-4; and Fig. 274a 



Ice Age, 9, 283-4, 290. See also Glaciation 



Iceland, 121 



Induced apogamy, 6, 21, and ch. 12 



in Doodia caudata, 198-204; and Fig. 202a 



in Scolopendrium vulgare, 204-7 

 Indusium, shape, 46, 54 



absence of, 63, 81, 94-5, 128 



in Asplenium, 93 

 International Rules of Nomenclature, 48 

 Ireland, 48, 59, 69, 73, 134, 212, 223-31, 254, 270; 



and Figs. 224-8, 270 

 Isoetes, 17, 22, 244, 253-9, 286-9 

 /. echinospora, 254-5 

 /. hystrix, 255-9; «"^ Figs. 254-7 

 /. lacustris, 253-5; and Figs. 252, 253, 256a 

 Italy, 104, 125, 132, 174, 212-13, 259 



Janssens, 2 

 Jordanian species, 1 3 



Karpechcnko, 13 



313 



