Glossary and Index. 1 1 1 



D. 



Decurrent, (tie, down, and currere, to run), prolonged on the rachie. 



Deer-fern, Vide Lomaria. 



Deltoid, (Gr. ddta, the letter D, and eld^s, form), triangular like the Greek delta. 



Dentate, {dens, a tooth), toothed. 



Denticulate, {denticidus, diminutive of dens, tooth), finely toothed. 



Devonian Age, Number of American species of ferns, 25. 



Dichotomous, (Gr. dlcha, asunder, and temnein, to cut), two-forked. 



Dicksonia, (Named for James Dickson, an English Botanist, 1738—1822), a genus 

 of 44 species, nearly half of which are arborescent. 96 ; also 20, 35, 64. ^ 



Dicksonieae, 51, 64. 



Dimorphism, 18. 



Dimorphous, (Gr. dis, twice, and morpke, shape, form), of two forma ; said of ferns 

 whose fertile fronds are unlike the sterile. 



Distichous, (Gr. dis, twice, and stlchos, a row), disposed in two rows. 



Distribution of Ferns. Climatic, 22 ; Geographical, 21 ; GeologicaI,-24 ; Local, 19, 23. 



Dorsal, {dorsum, the back, pertaining to or situated on the back. 

 E. 



Ebeneous, (d)enus, ebony), black like ebony. 



Endospore, (Gr. endon, within, and sporos,& seed), the inner wall of the spore. 



Epidermis, ^Gr. epi, upon, and derma, the skin), the external covering of a plant. 



Epiphytic, (Gr. epi, upon, and pAuiore, «. plant), growing upon another plant, but 

 not nourished by it. 



Equisetaceae, {equzLS, horae, and seta, bristle), the scouring rushes, or horse-tails, 

 50, 103. 



Exospore, (Gr. exo, outside, and sporos, a seed), the external covering of the spore. 

 F. 



Falcate, (falx, a sickle), scythe-shaped; slightly curved upward. 



Farinose, (farina, ground corn), covered with a white or yellowish powder. 



Ferruginous, {ferrum, iron), resembling iron rust. 



Fertilization, .38. 



Fibrillose, {jlbva, a thread), formed of small iibres. 



Filices: Characters of, 17,61; Classification of, -51 ; Definition of, 17; Distribution 

 of, 11, 21 ; Fossil, 25 ; Position in Vegetable Kingdom, 48. 



Filiform, (filum, a thread, /orTwa, form), thread-like. 



Flabellate, C^ofteWum, a fan), fan-shaped; broad and rounded at the summit and 

 narrow at the base. 



Flaccid, (Jlaccits, flabby), soft and weak. 



Floating-fern. Vide Ceratopteris. 



Flowering-fern. Vide Osmunda. 



Foliaceous, {folium, a leaf), having the nature of a leaf. 



Fossil-ferns, 25. 



Frond, {frons, a leafy bough), that which answers to the leaf in ferns. 20, 42. 



Fruiting, Time of, in ferns, 19. 



Fulvous, (fvZvits, reddish-yellow), tawny. 



G. 



Genera, 47 ; Number of, 52. 



Generic Names, 45. 



Geographical Distribution of ferns, 21. 



Geological Distribution of ferns, 24. 



Germination, 37, 56. 



