CONCERNING NOMENCLATURE. "298 
POLY PODIACE. 
Sporangia stalked, borne on the back or 
margin of the frond, opening transversely ; 
ring vertical and elastic; rootstock short 
or extensively creeping; fronds scattered 4 Side view 
or clustered ; prothallia green, not subter- — paypaywoe 
ranean. 
TRIBES AND GENERA. 
TRIBE I.—POLYPODIEH. GENUS. Polypodium. 
TRIBE II—GRAMMITIDER, GENUS. WNotholena. 
TRIBE III._—PTERIDE& GENERA. Adzantum, Pterts, Chet- 
lanthes, Pellea, Cryptogramma., 
TRIBE [V.—BLECHNE&. GENUS. JVoodwardza. 
TRIBE V.—ASPLENIE&, GENERA. Asfplenzum, Athyrium, Scolo- 
pendrium, Camptosorus. 
TRIBE VI.—ASPIDIE®. GENERA. Phegopterts, Aspidium, Poly- 
stichum, Cystopterts, Onoclea, Struthiopterts. 
TRIBE VII.—WoopDsIE#. GENUS. Woodsza. 
TRIBE VHI.—DICKSONIEA. GENUS. Dachsonza. 
In the early days of botany, plants were named in a 
very loose and haphazard manner and several more or less 
descriptive words were usually combined to form the 
name of each species. These cumbersome titles were 
in common use until the time of Linnzus, but that 
acute naturalist perceiving the advantage of shorter and 
more exact names originated a system of naming both 
animals and plants in which the name of each kind 
consists of but two words; the first or group name 
standing for the family and the second or individual 
name standing for the species. 
Linnzus was not the first to have a clear conception 
of genera and species, nor yet the first to give a double 
