48 



LIST OF THE BKITISH 



XXI. DlCTYOSIPHON. 



Frond filiform, tubular, branched. Spores irregularly 

 scattered, solitary, or in dot-like sori. Root a small, 

 naked disk. 



1 . Dictyosiphon fceniculaceus. 



XXII. Stkiaria. 



Frond filiform, tubular. Spores in dot-like sori, 

 ranged in transverse lines. Root naked and scutate. 



1. Striaria attenuata. 



XXIII. Punctaria. 



Frond flat, leaf-like. Spores scattered over the whole 

 frond, in minute, distinct dots, 



1. Punctaria latifolia. 



2. plantaginea. 



3. ,, tenuissima. 



XXIV. Asperococcus. 



Frond membranaceous, tubular, or compressed. 

 Spores in dot-like sori. Eoot minutely scutate, naked. 



