WOODSIA. 
187 
are almost concealed. The stipes is also scaly, and, as 
occurs in a whole group of these Woodsias, has a joint or 
articulation at a short distance from its base, at which 
point separation takes place if the fronds are left to attain 
a good old age, the lower part remaining attached to the 
caudex, while the upper part falls away. The veining of 
the segments of the pinnm consists of a rather indistinct 
midvein, from which the veins, either simple or branched 
proceed towards the margin, near to which the sori are 
produced. 
There seems no reasonable doubt that the Fern which 
Linnseus called Acrostichum ilvense is that now under 
notice. It has also been called Polypodium ilvense. 
Woodsia alpina, Gray. 
The Blunt-leaved , or Alpine Woodsia. 
(Plate IV. fig. 1.) 
This is a diminutive species, never exceeding a few inches 
in stature, and renewing its fronds annually in the spring, 
the older ones being destroyed by the frosts and cold of 
winter ; when this influence is felt by the plants, the fronds 
quickly lose their vitality, and are cast off at the articulation 
or joint near the base of the stipes, which occurs in this 
