Ld 
which is epiphytic on trees and much subject to t 
VITTARIA LINEATA 195 
Gametophyte capable of indefinite growth and duration, branch- 
ing irregularly or bifurcating into numerous lobes, which are pro- 
liferous by gemmae borne from podetia, usually on marginal cells ; 
serving to propagate the plant asexually, and also rendering it au- 
toicous by bearing antheridia ; archegonia borne on the under side 
of the thallus. 
Sporophyte forming rudimentary leaves, 1-4 cm. long, spathu- 
late, with a single central vein ending below the apex or forming 
a loop in the rounded apex ; rhizome short, divided, creeping, spar- 
ingly, densely covered with lanceolate, serrate, filiform-pointed 
scales, with papillose walled cells; leaves dark green or glaucous, 
two-ranked, crowded in dense compact pendent tufts, often 2-3 ft. 
long, 2-3 mm. wide, coriaceous, three-veined, the midvein pinnate 
and anastomosing with the lateral veins, with a deep sporangial 
groove over each lateral vein, in which the stomata are borne, 
paraphyses branching twice, usually forking, cylindric, the end cells 
curved and larger, brown; spores reniform, smooth, .027 X .054 
m 
Florida, as far north as St. Augustine ; also credited to South 
Carolina by Fée and Hooker, but probably by mistake. Pre- 
sumably the same as the West Indian species, of which the game- 
tophyte is still undescribed, and the microscopic structure imper- 
fectly known. 
GAMETOPHYTE * 
PROTHALLIUM.—(F. 1-38). The gametophyte of Vittaria 
lineata is an irregularly branched prothallium (Y. 1-4), consist- 
ing of a single layer of distended cells containing chlorophyl (f. 
14, 15). New prothallia may arise from any one of the marginal 
cells, or from two or more of the lamellar cells of the prothallium 
(f. 5-8). This capacity for vegetative reproduction by prolif- 
eration of the prothallus must be of great service to this species 
he attack of small 
animals. Almost any fragment of the prothallus might continue 
growth independently. 
The younger portions of the prothallia assume à horizontal 
position at right angles to the trunk of the tree to which they are 
attached, extending to a distance of 9 mm. in some instances. As 
the formation and growth of rhizoids proceeds successively in 
based was collected by Miss 
he bark of the palmetto. 
* The material on which the anatomical study is 
Abbie M. Small at St. Augustine, Florida, 22 Feb. 1901, ont 
.* 
