POLYPS AND CORALS. 67 



coarse sand, but rising atbove it when extended, March, 

 1855. Dr. William Stimpson. 



ANTHOPLEURA, sp. 



A species resembling the preceding. Simoda, Japan. 

 Dr. William Stimpson. 



FAMILY, THALASSIANTHID^;. 



Thalassianthidce Verrill, these Proceedings, IV, p. 148, 1865 ; Trans. 

 Conn.,Acad., I, p. 461, 1869. 



This family includes a great variety of forms, remark- 

 able in having branchiform organs which arise from the 

 disk, either within or outside of the circle of simple ten- 

 tacles, intermixed with them, or even wholly taking 

 their place. These organs may be simple or variously 

 lobed tubercles, or they may be elongated and variously 

 branched and subdivided, foliaceous or arborescent, and 

 often much larger than the true tentacles. 



SUBFAMILY, PHYLLACTIN^E. 



Phyllactince Edw. and Haime, Corall., I, p. 291, 1857; Verrill, 1. c., 

 p. 462. 



Actinians having both simple tentacles, and compound, 

 arborescent or foliaceous, tentacle-like, organs on the disk, 

 among the simple tentacles, or at the margin of the disk, 

 and homologous with the marginal verrucae of JBunodes, 

 and other" genera. These probably have the nature of 

 branchiae. 



AMPHIACTIS Verrill, gen. nov. 



Base broad. Column covered with prominent verrucae, 

 arranged in vertical lines. Simple tentacles in several 

 rows submarginal, with compound and much subdivided, 

 short, tentacle-like organs both outside and inside of 

 them; the latter covering the disk more or less com- 

 pletely. 



This genus differs from Oulactis in having complex 



