62 McMURRICH. (VoL. III. 
corresponding pair, as in Palythoa, consists of two macrosepta. 
The former arrangement he terms the microtypus, and the latter 
the macrotypus. 
12. Zoanthus sociatus (Ellis), Lesueur. (Pl. II., Fig. 3; Pl. 
IV., Figs. 15-18.) 
Synon. — Actinia sociata— Ellis, 1767. 
Zoanthus sociatus — Cuvier, 1817. 
Zoanthus sociata — Lesueur, 1817. 
Zoanthus socialis — Blainville, 1830 (teste Andres). 
Zoanthus Ellisii— Bosc, 1802. 
Zoantha nobilis — Duchassaing and Michelotti, 1860. 
This is one of the earliest non-European Actinians which has 
been described, Ellis having described it in 1767. His descrip- 
tion, however, is principally anatomical, and sufficient is not 
given to distinguish it from other species of Zoanthus. In the 
edition of Ellis’ studies on the Corallines compiled by Solander 
(’86) it is suggested that this form may be identical with the 
“‘Waterbottles ” described by Hughes in his Natural History of 
the Barbadoes, published in 1750. Lesueur (17) employed 
Ellis’ name for a species which he characterizes with consider- 
able clearness, and there is little doubt but that the form 
described below is identical with his species. Duchassaing and 
Michelotti (60) describe a form, 7. zodzlis, giving as a synonym 
for it Z. soctata (Les.), and stating that their form differs from 
Lesueur’s in having the tentacles longer and more numerous, 
and of a blue color, instead of yellow ; but it seems probable 
that the two are identical, the difference in coloration being 
comparatively unimportant. Bosc’s name was applied to the 
Actinia sociata of Ellis. 
This species was very common at New Providence, growing 
in masses as much as 15 cm. in diameter. It seems to be 
widely distributed throughout the West Indies, since, if the 
synonomy given above be correct, it has been described from 
Barbadoes, Dominica, and Guadaloupe. In color (Pl. IL., Fig. 3), 
the stolon and lower part of the column is usually flesh-colored, 
while the upper part of the column is purplish brown; the 
tentacles are the same color as the upper part of the column, 
while the disc is bright green, sometimes varying to peacock- 
blue or pale bluish green; in many forms there were two tri- 
