114 Our Native Ferns. 



Petiole, {'peiiohi^, diminutive of pes, foot), the stalk of a pinna or pinnule. 

 ' Phegopteris, {Gt. pliegos, a beech-tree, and pteris, a fern), contains 95 species. 87; 

 also 20, 27, 33, 63. 



Pilose, {pUus, hair), covered with soft hairs. 



Pinna, (Lat. a feather), the primary division of a compound frond. 



Pinnate, (pinna, a feather), having the divisions of the frond arranged on the two 

 sides of a common rachis. 



Pinnatifid, {pinna, a feather, And findere^ to cleave), having the sides of the frond, 

 pinna, or pinnule, cut half way or more to the midvein. 



Pinnule, {pinnula diminutive of pinna, a feather), the secondary division of a frond 

 twice or more compound. 



Polypodiaceffi, 28, 61. 



Polypodiese, 52, Gl. 



Polypodium, (Gr. polus, many, and pcym, foot, alluding to the branching rhizoma), 

 the largest, most cosmopolitan genus of ferns; containing 345 species, 68; also iil, 27, 

 28*, 30, 36* 61. 



Pro-embryo, the thread-like prolongation between the germinating spore and the 

 prothallium. 



Prothallium, (Gr. pro, previous to, and thallos, a young shoot), the sexual genera- 

 tion of a fern, 37. 



Pterideae, 51, 62. 



Pteridoid, (Gr. pteris, fern, and ddos, form), fern-like in appearance. 



Pteridophyta, (Gr, pieris, fern, and p/iMton, plant), ferns and their allies; a syn- 

 onym of Vascular Cryptogams. Classification of, 50; Geological Distribution of, 50; 

 List of, 103. 



Pteris, (Gr. pteris, a fern, from ptermi, wing, alluding to the prevalence of pinnate 

 fronds), a cosmopolitan genus the type of PterUlese, containing 103 species. 74; also 20, 31, 

 37* 38*, 62. 



Q. 



Quadripinnate, {quoUuor, four, andpijma, feather), four times pinnate. 



Quadripinnatifid, {tpwUuor, four, pinna, a feather, and findere, to cleave), four 

 times pinnatifid. 



R. 



Rachis, (Gr. the spine), the continuation of the stipe through a compound frond. 



Rattlesnake-fern. Ff'iie Botrychium. 



Receptacle, {recipere, to receive), the part to which the sporangia are attached es- 

 pecially in the Hymenophyllacb^. 



Reniform, {renes, the kidneys), kidney-shaped. 



Revolute, {revolvere, to roll back), rolled backward ; said of the margin of many 

 fronds. 



Rhizoma, (Gr. rhiza, a root), a rootstock, or underground stem, usually creeping at 

 or below the surface of the earth, 26. 



Rhomboidal, (Gr. r/iomfios, a rhomb, and eidos, form), approfiching a rhomb in 

 shape. 



Rock-brake. Vide Cryptogramme. 



Roots, 41. 



s. 



Scandent, {scandere, to climb), climbing. 



Schizaea, (Gr. schizein, to split, alluding to the forked sterile fronds of foreign spe- 

 cies), contaiDS 16 species. 98; also 29*, .^6*, 36*, 64. 

 Schizaeacese, 29, 64. 



