182 HISTORY OF BRITISH FERNS, 



is lanceolate, more or less broad, and in their mode of divi- 

 sion they are pinnate, the pinnae usually set on nearly or 

 quite opposite in pairs, and having an obtusely oblong out- 

 line, with a deeply -lobed or pinnatifid margin. They are of 

 a thick dull-looking texture, and are more or less clothed on 

 both surfaces, but especially on the veins beneath, with 

 minute bristle-like scales, and shining jointed hairs, among 

 which the sori 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 

 on to attain a good old age, the lower part remaining at- 

 tached to the caudex, while the upper part falls away. 



The veining of the segments of the pinnse consists of a 

 rather indistinct midvein, from which the ven tiles, either 

 simple or branched, proceed towards the margin, near to 

 which the sori are produced. 



There seems no reasonable doubt that the Fern which 

 Linnaeus called AcrosticJium Uvense is that now under notice. 

 It has also been called PoJ/ypodium Uvense. 



