213 
Stuckey and C. plicata Hutton together with Saccactis. The “fronds** 
in these two species are namely nothing but aggregates of suck- 
ing warts (Urticina-werrucae) and no nematocyst-batteries. Stuckey 
also States (1909c p. 393) concerning C. plicata that “the lobes 
of the fronds are able to act as suckers“. Cradactis magna and 
plicata are thus to be placed in the family Cribrinidae (Bunodac- 
tiidae) or Actiniidae (if in conformity with Stephenson we join the 
both families to one). As the type-species of the genus Cradactis 
is imperfectly described but as it is probable that the “fronds“ here 
are batteries of nematocysts and not sucking warts, I have pre- 
ferred to propose a new genus Isocradactis for Cradactis magna 
and C. plicata. If, however, it should appear that the genus Cra¬ 
dactis and Isocradactis are identical, the genus Saccactis must at 
any rate be kept, as I cannot agree with Stephenson in his sup¬ 
position that the sucking warts are predecessors to the vesicles 
(1921 p. 500, 1922 p. 282), In such a case we should namely 
have to presume a change of function of the warts, accompanied 
by a re-appearance of the nematocysts, which are lacking in the 
apex of the warts. It seems more probable that these formations 
are developed independantly of each other, Besides, it is a pity that 
Stephenson (1921 p. 500) uses the term acrorhagi “to cover 
marginal sphaerules of any sort whether simple or compound, 
whether nematocyst-batteries or not“. This leads to a confusion of 
almost the same kind as that concerning the terms “suckers“, 
which has been used for so different formations as Halcampa- 
papillae, ^/-fc'/za-verrucae, elevations of cinclides and other papillae 
of various structure on the body-wall. 
Isocradactis magna (Stuckey). 
Cradactis magna n. sp. Stuckey 1909 c p. 394. 
Di agn os i s. Column cup-like. “Fronds** with very numerous 
•sucking warts, especially in the endocoelar parts of the column, 
where their number amounts to considerably more than 100. 
Sphincter diffuse, in comparison with the size of the body rather 
weak. Tentacles, at least in contraction, distinctly longitudinally 
furrowed, about 192. Mesenteries about 96 pairs of which 2 pairs 
of directives, almost all perfect. Nematocysts of the column 12—14 
