124 ZOOPHYTES. 



The genera of Actinidae are characterized as follows : 



I. Tentacles not in any part papillose or laciniately lobed. 



A. Tentacles simple, wittiaut suctorial vesicles. 



GENUS I. ACTINIA. (Linn.) Tentacles simple, retractile, sometimes 

 obsolescent; attached at base. (Includes the Discosoma of Leuckart, 

 the Actinoloba and Actinocereus of Blainville, the Cribrina of Ehren- 

 berg.) 



GENUS II. ANTHEA. (Johnston.) Resembling Actinia, but the ten- 

 tacles not retractile. (Johnston's British Zoophytes, 220. The name 

 is from avdos, a flower.) 



GENUS III. CAPNEA. (Forbes.) Body cylindrical and invested with 

 a thick lobed epidermis, adhering by a broad base ; tentacles simple, 

 very short. (E. Forbes, Esq., Mag. Zool. and Bot. vii. (1840) 

 80. The genus is near the Zoanthidse.) The name is from x <x*vi, 

 chimney. 



GENUS IV. ILYANTHUS. (Forbes.) Resembling Actinia, but body 

 tapering to a point below, and probably free or buried in the mud : 

 tentacles simple, retractile. (E. Forbes, Esq., Mag. Zool and Bot. 

 v. 180, (1840). The name is from i\ vs , mud, and avdos, flower.) 



GENUS V. EDWARDSIA. (Quatrefages.) Free, vermiform, middle 

 part covered with an epidermis more or less thick arid opaque ; lower 

 extremity transparent, rounded, arid this, as well as the upper ex- 

 tremity, retractile. (A. de Quatrefages, Ann. des Sci. Nat. xviii. 

 (1842) 65. The genus may be near the Zoanthidae. May be identi- 

 cal with the Moschata of Renieri ?). 



GENUS VI. ACTINECTA. (Blainville.) Near Actinia in general 

 form, but free, and having an air cavity, and cellular float, in the base 

 of the animal. (Blainville, Man. d'Actin. p. 318. The name of the 

 genus is from actinia and necto, to swim. This genus includes the 

 Minyas of Cuvier, which was incorrectly characterized. Ehrenberg 

 also refers here the Moschata of Renieri, a free, vermiform Actinia, 

 having many of the characters of the Edwardsia of Quatrefages.) 



B. With suctorial vesicles upon Hie. tentacles or disk. 



1. Margin of disk not deeply lobed. 



GENUS IV. EPICYSTIS. (Ehrenberg.) Tentacles not branched, part, 

 or all of them, or the disk, furnished with suctorial vesicles. (Ehren- 

 berg, Berlin Trans. 1832, p. 268. Includes the Actinodendrum of 

 Ehrenberg, but not of Blainville.) 



GENUS V. ACTINODENDRUM. (Blainville.) Tentacles branched, ex- 

 tremities enlarged and covered with numerous suctorial (?) vesicles 

 (Blainville, Man. d'Actin. p. 320.) 



