THE MARINE BOTANIST. 159 



DELESSERIA SINUOSA.— OAK-LEAVED 

 DELESSERIA. 



Fronds irregular in their outline, jag-ged, with a 

 clear, well-defined midrib. Colour, claret-red ; 

 not so bright as the preceding, nor does it adhere 

 to paper so firmly. The tubercles are embedded 

 in the midrib of the leafy lobes ; tetraspores in 

 minute slender processes fringing the margin. 

 Growls frequently on the stems of L, digitata, 

 likewise attached to various substances in deep 

 water, and vegetates at a depth varying from six to 

 ten fathoms. Perennial. Summer and autumn. 

 Common on the British shores. 



DELESSERIA ALATA.— WINGED 

 DELESSERIA. 



Stem somewhat forked, and much branched. 

 Fronds not in a leaf-like form, but continuing along 

 each side of the branches. Tubercles attached to 



