134 NATURE STUDY. 
tongue had the least complex structure of any fern-ally. 
The cellular cryptogams, or bryophytes, and the vascular 
cryptogams, or pteridophytes, here approach each other very 
closely, as closely as could have been expected considering 
the immense number of intermediate forms which must 
have perished in the struggle for exist¬ 
ence. 
The little plant called by the unpleas¬ 
ant name is thus intensely interesting, both 
as a connecting link between two grand 
divisions in the plant world, and as the 
simplest vascular plant known to exist. As 
you will see from figure i, it consists of 
a root, stem and leaf. The leaf is in two 
portions, called the fertile and the sterile 
segments. The sterile segment is a leaf¬ 
like expansion; the fertile segment is a sort 
of spike, bearing the coalescent sporangia 
in a double row. This type is pretty close¬ 
ly adhered to in all the species, though 
there is a curious exception in O. palmatum 
which has the sterile segment palmately 
divided. We possess locally the single, al¬ 
most cosmopolitan, species O. vulgatum. 
In the West and Northwest are found two 
or more additional species, and the pros¬ 
pect is that more may be added as further 
explorations are made in those regions. 
Were the family represented with us 
only by the genus Ophioglossum we should be likely to 
consider it very restricted and in a fair way to become ex¬ 
tinct at no distant date. The allied genus Botrychium 
shows signs of greater adaptability to modern conditions. 
Both by the vastly greater number of individuals it pro¬ 
duces and by the polymorphic character it manifests within 
Fig. 3. 
