INDEX 



Adiantum pedatum, 33-39; unilateral ve- 

 nation in, 24, 25; explanation of odd 

 leaflet on rachis, 9, 35, 36. 



Amesium, 30. 



Asoidium ; acrostichoides, see Polystichum 

 acrostichoides; marginalis, see Dryopteris 

 marginalis; noveboracense, see Dryop- 

 teris noveboracensis; spinulosum, var. 

 intermedium, see Dryopteris spinulosa 

 intermedia. 



Asplenium ; acrostichoides, see Athyrium 

 thelypteroides ; angustifolium, 63, 67, 

 diplazioid sori in, 66, 67, 72; ebeneum, 

 see A. platyneuron; ebenoides, 6; ger- 

 manicum, 30; platyneuron, 77-81, same 

 changes during its leaf development 

 under different conditions of environ- 

 ment, 7, 8, early stages of its leaf com- 

 pared with those of A. trichomanes, 73, 

 80; ruta-muraria, see Belvisia ruta-mura- 

 ria; septentrionale, 30; thelypteroides, see 

 Athyrium thelypteroides; trichomanes, 

 71-74, early stages of its leaf compared 

 with those of A. platyneuron, 73, 80. 



Athyrioid sori, formation of, 103, 104; their 

 occurrence in the silvery spleenwort and 

 other species of Athyrium, 104; their 

 possible occurrence in any species of 

 Asplenium, 104. 



Athyrium; acrostichoides, see A. thelyp- 

 teroides; cyclosorum, 104, 105; filixfcem- 

 ina, 104, 105 ; thelypteroides, 99-105. 



Belvisia; the genus, 30; ruta-muraria, 

 27-30. 



Camptosorus rhizophyllus, 131-134, early 

 venation of, 18, 133, auricles of the leaf 

 partly formed pinnae, 12, 133, 134. 



Christmas fern, see Polystichum acrosti- 

 choides. 



Crvptogramma Stelleri, 93-96. 



Development of the fern leaf ; modes of, 

 1-26; in connection with different kinds 

 of venation, 925, see also Venation; in 

 given species, see chapters under species' 

 names ; retarded by low vitality of the 

 plant, 5, 6; set back by an injury to the 

 plant, 6; fluctuating in parts of flie leaf, 

 3, 4; affected by conditions of environ- 

 ment, 6, 7, 88, 89; carried beyond its 

 usual limits under certain conditions, 7, 

 88, 89, 115; supposedly specific characters 

 of the leaf sometimes features of only 

 certain of its stages, i, 115; mature stages 



and stages at which sori appear, 4, 5; cer- 

 tain changes and the appearance and dis- 

 appearance of certain peculiarities in the 

 leaf indicating ancestral characteristics, 

 8, 9; monstrous, 26, in the maidenhair, 

 39, in the polypody, 50, 52, 53, in the 

 narrow-leaved spleenwort, 65, 66, in the 

 maidenhair spleenwort, 74, in the ebony 

 spleenwort, 81, in the hart's-tongue, 43. 



Diplazioid sori, in the ebony spleenwort, 81 ; 

 in the narrow-leaved spleenwort, 66, 67; 

 in the silvery spleenwort, 100, 103-105. 



Dryopteris; possible evolution of the ge- 

 nus, 105 ; acrostichoides, see Polystichum 

 acrostichoides; goldieana, 64 ; margina- 

 lis, 119-122; noveboracensis, 109, no, 

 its leaf-development compared with that 

 of D. simulata, no; simulata, 113-115, 

 found with Lorinseria areolata, 114, 139; 

 spinulosa intermedia, 125-128; thelypte- 

 ris, means of distinguishing it from D. 

 simulata, 115, its resemblance to Athy- 

 rium thelypteroides, 105. 



Ebony spleenwort, see Asplenium platy- 

 neuron. 



Flabellate venation, see Venation. 



Hart's-tongue, see Phyllitis scolopendrium. 



Lorinseria; the genus, 142; areolota, 137- 

 142, found with Dryopteris simulata, 114, 

 139, resemblance of its early stages of 

 leaf development to those of Onoclea 

 sensibilis and Osmunda spectabilis, 139, 

 147, its relationship to Onoclea sensibilis, 

 139, 147, 150, 151, its leaf -development 

 compared with that of O. sensibilis, 119, 

 150, its venation compared with that of 

 O. sensibilis, 140, 141. 



Maidenhair, see Adiantum pedatitm. 



Maidenhair spleenwort, see Asplenium 

 trichomanes. 



Marginal shield-fern, see Dryopteris mar- 

 ginalis. 



Massachusetts fern, see Dryopteris simu- 

 lata. 



Narrow-leaved spleenwort, see Asplenium 

 angustifolium. 



Nephrodium; marginale, see Dryopteris 

 marginalis; noveboracense, see Dryop- 

 teris noveboracensis; simulatum, see 

 Dryopteris simulata; spinulosum, var. 

 intermedium, see Dryopteris spinulosa 

 intermedia; thelypteris, see Dryopteris 

 thelypteris. 



155 



