252 Postelsta 
unless’ it be depth of water; holdfast, the 
simple primitive disc enlarged, without any 
trace of hapteres arising higher up “onthe 
stipe, though often in the disc itself showing 
local secondary growth, manifesting itself as 
radial thickenings and even closely appressed 
branches. (Plate Ill; Fis. 2), asas<alsethieeace 
in Cymathere triplicata but not so conspicuous 
as in that plant. The largest holdfast collected 
measures about 20 millimeters in width; often 
they are much smaller not exceeding 8 milli- 
meters. Mucilage ducts are absent from both 
stipe and lamina. 
Fruiting habits very variable; sometimes 
very small apparently young specimens are 
found in fruit. I have specimens with well 
developed sori the dimensions of which are 
as follows: (a) (Plate X VI., Fig. 10) lamina 8x3.3 
centimeters, sorus orbicular, about 25 milli- 
meters in diameter, stipe 35 millimeters, hold- 
fast 7 millimeters; (b) (Plate XVI., Fig. 2) lamina 
12.5 x 2 centimenters, sorus elliptical 37am 
millimeters, stipe 4 centimeters, holdfast 7 
millimeters. On the other hand I have several 
