INDEX 
Adiantum 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 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; filix foem- 
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 pinne, 12, 133, 134. 
Christmas fern, see Polystichum acrosti- 
choides. 
Cryptogramma Stelleri, 93-06. 
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 the 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, 1, 115; mature stages 
155 
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, 110, 
its leaf-development compared with that 
of D. simulata, r10; 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 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. 
