144 HISTORY OF BRITISH ZOOPHYTES. 



Mr. Hassall in considering Ms A. ramosa as a good species ; 

 though there is another (slightly) branched state of A. an- 

 ten-nina, unquestionably a mere variation, being provided 

 with the tubular cells above alluded to. 



Genus VIII. PLUMULARIA, Lamarck. 



Gen. Char. Polypidom plant-like, rooted, simple or branched, 

 the shoots and offsets plumous : cells small, sessile, unilateral, 

 usually seated in the axillae of a horny spine ; vesicles scattered, 

 unilateral. Polypes hydraform. Dr. Johnston. 



* Stem a single tube. 



1. PLUMULARIA FALCATA, Sickle Coralline, Merrit. 

 (Plate VIII. fig. 22.) 



Hab. On shells and rocks near low-water mark, and in 

 deep water. 



" This elegant feathered coralline adheres to rocks and 

 shells by little wrinkled tubes, and rises from them into 

 erect stems, which are surrounded from bottom to top with 

 pinnated branches ; the smaller divisions of these have rows 

 of little denticles or teeth or cells on the side, and bend 

 inwards, as they become dry, in the form of a sickle." 



