RATTLESNAKE FERN AND ADDER’S-TONGUE. 47 
primitive way of bearing spores than is found in 
most ferns and is considered an indication that the 
Ophioglossums are very ancient forms. 
The rootstock is short and produces many short fleshy 
roots. Here and there adventitious buds may be formed 
upon them and new plants result. In some species in 
this genus, this is said to be the chief method of propa- 
gation. The prothallia are apparently seldom developed, 
perhaps because this way of getting new plantsis so 
much surer. The curious manner in which the adder’s- 
tongue appears and disappears in the same spot in differ- 
ent years has given ground for the belief that the plants 
occasionally rest for aseason. Itis also conjectured that 
the prothallia may form resting bodies as the prothallia 
of certain other species of ferns are known to do. , 
In 1897 a party of botanists found a colony of small 
Ophioglossums in southern New Jersey, specimens of 
which were subsequently described as O. arenarium. 
This is apparently only a depauperate form of the com- 
mon species due to the sterile soil in which it grows. It is 
described as about half the size of vu/gatum with a rather 
lanceolate sterile portion in which there are from five to 
seven basal veins. The describer writes of it “It seems 
a little difficult to tell some of the young fronds of 
O7. vulgatum from the mature ones of O. arenarium, and 
yet the extremes are so different and the habit and 
habitat so distinct that I have concluded to retain them 
as separate species. That O. arenartum has originated 
from O. vulgatum and that intermediate forms may be 
found in young or poorly developed specimens, does not 
alter the view from the modern standpoint of evolution.” 
It is probable that the majority of botanists would con- 
sider this more properly placed as O. vulgatum arenarium 
and not as a separate species. 
