THE BLADDER FERNS. 
22 I 
the lowest pair of branches on the frond, and 
coming to those immediately above them, we 
find that this pair, besides being much smaller, 
has not the same disproportion between the upper 
and lower leaflets, although those of the upper 
row are somewhat shorter than those of the lower 
one. On this second pair of branches the leaflets 
near the main rachis are more deeply cleft than 
those away from it towards the point of the 
branch. The same process of gradual diminution 
goes on towards the highest point of the frond, 
branches becoming shorter and less divided until 
they merge into leaflets, which in their turn 
become shorter, smaller, and less cleft or serrated, 
until they merge in the extreme tip of the frond 
itself. The general shape of the frond, including 
the whole of its leafy portion, is triangular ; each 
of the lowest pair of branches is also triangular ; 
the other branches are first lance-shaped, and as 
they merge into leaflets, these become somewhat 
egg-shaped. The distinct lobes of the leaflets, 
near the main rachis on the lower part of the first 
pair of branches, are also somewhat egg-shaped. 
