444 Farmer and Freeman. — On the Structure and 
the former genus, whilst in respect of its foliar bundles it shows 
more affinity with the latter, especially with O. pendulum. 
Again, whilst it differs from both in respect of the complexity 
of its sporangia, it merely forms in this respect a member of 
a series which can be constructed with Ophioglossum as its 
starting-point, and passing on through Botrychium. 
It is a matter for regret that material for the study of the 
prothallium was altogether lacking ; it would be of the greatest 
interest to know whether the antherozoids are multiciliate (as 
is probably the case) like those of the Ferns, or whether they 
exhibit a leaning to the biciliate type characteristic of the 
Lycopods. 
It would seem, however, that a near relation with the true 
Ferns, whether Eusporangiate or Leptosporangiate, is very 
doubtful. The stipulate character which might suggest 
Marattiaceous lines will not bear close examination, as the 
plants are in reality very different from each other in almost 
all important respects. Rather it would appear that, like 
some of the surviving species of Ophioglossum and Botrychium , 
Helminthostachys zeylanica represents a very old form ; and 
that, whilst retaining some of the ancient and more generalized 
characters which also recur sporadically in some members of 
the Lycopodineae, it has developed along lines sufficiently 
parallel with the other members of the Ophioglossaceae to 
justify its being united to this family: nevertheless it has 
also acquired a strong individuality of its own which tends 
to obscure almost any single link of relationship on which we 
may definitely concentrate our attention. 
