INDEX 



Adiantiun pedatum, 33-39; unilateral ve- 

 nation in, 24, 25; explanation of odd 

 leaflet on rachis, 9, 35, 36. 



Amesium, 30. 



Aspidium; 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 vrith 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; filixfoem- 

 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, 9-25, 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 fhe leaf, 

 3, 4; affected by conditions of environ- 

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

 usual limits under certain conditions, 7, 

 88, 89, lis ; supposedly specific characters 

 of the leaf sometimes features of only 

 certain of its stages, 1, 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, 1 14, 

 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 pedatum. 



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. 



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