PTERIDOPHYTES 
153 
medium that grows among the blocks of sporogenous cells and ramifies 
into every intercellular space (fig. 360). 
Gametophyte. The gametophyte is of the Lycopodium type. In 
Ophioglossum, which is regarded as the most primitive genus, the game- 
tophyte is a tuberous, subterranean body that gives 
rise to aerial green lobes that bear the sex organs. 
In Botrychium there is no aerial portion, the game- 
tophyte being completely subterranean and tuberous 
(fig. 361). In Helminthostachys the gametophyte is 
somewhat intermediate in structure, the tuberous body 
giving rise to a cylindrical aerial process that bears 
the sex organs. In every case the tuberous body 
contains an endophytic fungus, as in the gametophyte sum: diagrammatic 
of Lycopodium. It is evident that the gametophvte " OSS se , ction f f . er ' 
* f r J tile spike, showing 
of the Ophioglossales suggests that of the Lyco- t he two sporoge- 
podiales; but that the nous bands at 
sporophyte is more like ^ ere ? stages 
* J After BOWER. 
that of Filicales. 
Sex organs. The antheridia develop 
as usual among the eusporangiates, the 
inner cell, following the periclinal division 
of the superficial initial, giving rise to the 
spermatogenous tissue. The sperms are 
large, coiled, and multiciliate, a type not 
found among the Lycopodiales, but char- 
acteristic of the Filicales. 
The archegonium of Ophioglossum has 
a very short neck, the neck canal cells 
being only two in number, the same 
reduced number as in Equisetum. In 
Botrychium (figs. 362-365) the neck of the 
archegonium is long, but contains only 
FIG. 360. Portion of a nearly 
mature sporangium of Ophio- I ur nec k canal cells. 
giossum, showing the tapetal Embryo. In general there is no sus- 
plasmodium (with nuclei) among b . fa fl described 
the groups of mother cells. . . 
After BOWER. Sceptridium a passive suspensor is re- 
ported, at least for one species (formerly 
Botrychium obliquum). There is no differentiation of the great body 
regions at the quadrant stage, but in Botrychium, for example, there is 
