No. 415.] NORTH-AMERICAN INVERTEBRATES. 581 
oral margin. Color: manubrium, yellow or cream-color, base of tentacles 
purplish. Male often with green manubrium. Hydroid (?). 
Stomotoca rugosa Mayer. 
General form of the medusa similar to the preceding ; ica) projection 
sometimes long, sometimes short and blunt; size about five mm. in height 
by three mm. broad ; two long marginal laici and 
fourteen rudimen pists ones; radial canals four; velum 
well developed. Distinguished from S. apicata in part 
by the distinctively different color, which in this 
species is of a brick-red at tentacular bases and manu- 
brium, while in the preceding (S. apicata) the manu- 
brium is greenish or straw-colored in the male and 
dull ochre in the female, and the tentacle bases in 
male are purplish and in female ochre. Hydroid 
generation, —a Perigonimus. 
Habitat: Common at Newport, R. I., and south- 
ward, 
(Condensed from Mayer’s description. Bull. Mus. 
Comp. Zoil., Vol. XXXVII, No. 1, P- 4.) 
Turris vesicaria A. Ag. (FIG. 41). 
Bell hemispherical, with large globular projection 
at its apex; marginal tentacles numerous; bases ' 
broad and with a single ocellus on each; tentacles 
tapering rapidly from the base and buisadie delicate 
and filamentous; manubrium large and with four 
fimbriated oral besi ; gonads borne upon the base 
of manubrium and even extending somewhat upon 
the radial canals, the walls of which are notched and 
variously irregular, as are also the walls of the mar- 
ginal canal. 
(Condensed from description of A. Agassiz, Wo. 
Am. Acalephe, p. 164.) 
Hydroid generation, — a Turris (?). Fic. 41. — Turris vesicaria 
A. Ag. (After A. Agassiz.) 
Turritopsis nutricula McCr. (FIG. 42). 
Bell high-hemispherical or subspherical ; radial 
canals four; velum broad; marginal tentacles 
varying from four to thirty or more, depending 
upon stages of ma turity; a reddish ocellus at Fic. 42. — Turritopsis nutricula 
S of tentacles; manubrium large but not ^ McCr. (After McCrady.) 
