INDEX 



Spartina, 4, 6 



Species concept, 51 



Spermatozoid (Frontispiece), 17, 19, 31, 266; 



and Figs. 6, 17, 265 b 

 Spindle, 34, 38, 164; and Fig. 167a 



tripolar, 238-40; and Figs. iSge, 234c 

 Spiral structure of chromosomes, 286 



description of in Osmunda, 34-5; and Fig. 21 



in Equisetum, 215; and Fig. 228 



in Hymenophyllum, 273; and Fig. 275 



in Leptopteris, 279; and Fig. 279 



in Psilotum, 240-1; and Fig. 236^ 



in Todea, 279; aW Fig. 279 

 Spleenwort. See Aspleniiim 

 Sporangium, 16-18, 32; fl«(/ Figs. 5c, 18 



development of, 162 



Doodia, apogamous and normal, 201; and Fig. 205 



in apogamous ferns, 163-9 



on prothalli, 196-7, 205 

 Spore, 16, 18 



germination in polyploids, 39-40; and¥igs. 26, 27 



in apogamous ferns, 22, 159, 163-8 



in Cystopteris, 1 1 8-2 1 ; and Fig. 1 1 8 



in Dryopteris Borreri, Fig. 20 1 



in Equisetum, 18; and Fig. 5 



sizes in D. Filix-mas complex, 47, 55; and Figs. 



39-41 

 Sporophyte, 18 



Squash techniques, 114, 178-9, 221 



details of the methods, 295-7 



examples of their use, 53, 63, 79, 100, 259 

 Staining methods, 294-7 

 Stange, 58, 198 

 Stansfield, 69, 72-3, 144 

 Steil, 159-60, 180 

 Stern, 2 

 Strasburger, 2 

 Sweden, 75, 109, 120-1, 126, 147-51, 248, 252; a?id 



Figs. 62, 69c, 97^, 119a, 247 

 Switzerland, 7, 55-6, 59, 65, 69, 75, 92, 100, 

 114, 121, 126, 133, 151-4, 189-91,247-8,259; 

 and Figs. 64, in, iigd, 155-7, 258 

 Symbiosis, 17, 236, 265 



Tavel, von, 55-9 



Technique, xi, 112, 293-9 



Telophase, definition, 34 



Thamnopteris, 276 



Thelypteris, 81, 85, 87, 108. See also Dryopteris 



Thelypteris 

 Tmesipteris, 22, 233, 235-36, 240-3, 285; and 



Figs. 238-40 

 Tobgy, 14 



Todea, 274, 276, 278-80, 286 

 T. Barbara, 278-9; and Figs. 278a, 279a 

 Tracheids, 16 



in apogamous prothalli, 197 



in Psilotum prothalli, 236-7 

 Trichomanes, 262, 270, 280 

 T. radicans, 270-2; and Figs. 270-2 

 Triploids 



definition, 5 



D. Filix-mas hybrid, 49-53; and Figs. 32-4, 37, 38 



in apogamous ferns, 195 



in Asplenium germanicum, 1 04-5 



in Biscutella, 7, 9 



in Dryopteris Borreri, 59-60, 189-92 



in Osmunda, 28-30, 34-42 



in Polypodium, 136, 138 



in watercress (Nasturtium) , 9-1 1 



Polystichum hybrids, 152-7 



Woodsia hybrid, 147-51 

 Trivalents, in Biscutella, 7-9; and Fig. 2e 



in Cyrtomium, 179-80; and Fig. 185 



in D. Filix-mas hybrid, 53; and Figs. 37, 38 



in Osmunda, 36-9; and Figs. 20b, 22c, 23, 27c 



in Pteris cretica, 175; and Fig. 177 

 Turesson, 44, 71, 290 



Uganda, 174-6, 177-9; a«^ Figs. 178, 179 



Univalents 



in apogamous ferns, 175, 183, 185, 187, 192; 

 and Figs. 171, 173c, 176, i-j^b, 189a, 192c, 

 194^, 196^*, 199-201 

 in Asplenium germanicum, Figs. 99, 100 

 in Biscutella, 7; and Fig. 2e 



in D. Filix-mas x D. abbreviata, 53 ; and Figs. 37, 38 

 in hybrid Equisetum, 228-31; and Figs. 226-8 

 in induced apogamy. Figs. 206, 209, 210 

 in Lycopodium Selago, 250-1; and Figs. 249, 250 

 in Ostrmnda, 37-9; and Figs. 22c, 23, 25 

 in other hybrid ferns. Figs. 57, 59 

 in triploid Polystichum, Figs. 158, 159, 161, 162 

 in triploid Woodsia, 149; an^ Figs. 153, 154 

 in watercress, g; and Figs. 3, 4 



Variation, 1-3 

 Vries, de, 3 



Wales, 48, 59, 103-7, iiO' 134. 251, 255; and Figs. 



97-9, loib, 1036, 107a, I lie 

 Watercress, 9-1 1 ; and Figs. 3, 4 

 Wettstein, von, 42 

 Winge, 13 

 WoUaston, 47-8, 55 

 Woodsia, 80, 1 10-12, 147-51 

 W. alpina, 110-11,147,1 49-5 1 , 286 ; and Figs. 107-9, 



i52e 

 W. alpina X W. ilvensis, 147-51; and Figs. 152-4 

 W. ilvensis, iio-ii; a W Figs. 107-9, '52 a 



Yamanouchi, 197 



Zalesskya, 276 

 Zea, 2 



316 



