ETYMOLOGY. 419 
Pleocnemia, pleos, full, knemia, rays; full of rays; the 
venation. 
Pleopeltis, pleos, full, peltis, shield; the sori being furnished 
with numerous round scales. 
Pleuridium, pleura, side (ribs); the primary veins being 
costeform, like ribs. 
Pleurogramma, plewra, side, gramma, a line; sori on the 
side of the mid-rib. 
Podopeltis, pous, foot, peltis, a shield ; the indusium. 
Pecilopteris, pækilos, spotted, pteris; the appearance of 
the venation. 
Polybotrya, polys, many, botrys, bunch; the fructification 
being in bünch-like racemes. 
Polypodium, polys, many, pous, foot ; polypus ; the rhizome, 
- when destitute of the fronds, having the appearance of 
some kind of sea-polypus. 
Polystichum, polys, many, stichos, order; not especially — 
applicable to the genus Polystichum, as now defined. 
Prosaptia ; sori immersed in the margin of the frond. 
Psomiocarpa, psomion, & small pellet, karpa, fruit; the 
sporangia being in small round patches, in spikes. | 
Pteris, pterye, wing ; the scientific name given to the plant 
known by the names of Brake, Bracken, and Fern; on 
. account of the supposed li 
its fronds to wings. This, being the commonest of all 
Ferns, has become the type of the whole race; hence 
Pteris means Fern, all generic names of Ferns ending } 
in pteris; 
= Dictyopteris netted Fern; also, if at the beginning of 
a book or writing on Ferns; 
|. a word, as Pteridography, 
= Pteridologist, à studier and writer on Ferns; Pieri- 
dophilist, a lover of Ferns. 
keness of the branching of ` 
such as Ceratopteris means horned Fern, 
