151 



GENUS I. AIPTASIA (Gosse). 



Anthea (Cocks). 



Base adhering to rocks, readily detached ; often not 

 equalhng the medium diameter of column. 



Column trumpet-shaped, many times higher than 

 wide, very changeable in shape from irregular disten- 

 sion ; margin tentaculate ; surface minutely corrugated, 

 adhesive, but without distinct suckers ; pierced with 

 loop-holes. Substance pulpy. 



Bisk greatly expanded, membranous, concave. 



Tentacles in several rows, long, lax, irregularly 

 flexuous, perforate at the tip, the first row longest, 

 scarcely retractile. 



Mouth not set on a cone ; lip thin ; stomach pro- 

 trusile. 



Acontia abundant, but not often spontaneously 

 extruded. 



The genus contains but one known species, 

 A. Couchii. 



