6 McMURRICH. [Vot. III. 
Genus AIPTASIA, Gosse. 
Synon. — Actinia (pars) — Auct. 
Cribrina (pars) — Schmarda. 
Dysactis (pars) — Milne-Edwards, 1857. 
Aiptasia — Gosse, 1860. 
Paranthea — Verrill, 1866. 
Bartholomea — Duchassaing and Michelotti, 1866. 
Sagartia (pars) — Jourdan, 1880. 
Sagartidz, with cinclides arranged in from one to several 
horizontal rows around the middle of the column. No verrucz. 
Sphincter muscle either absent or very feebly developed. 
Tentacles strongly entacmzeous. 
This genus was established by Gosse for A. Couchiz, and 
includes forms which have been variously assigned to the 
genera Sagartia, Actinia, Anthea, etc. In fact, not a little con- 
fusion exists with regard to the genus. Milne-Edwards (’57) 
established the genus Dysactzs, which he referred to his section 
of ‘ Actinines vulgaires,”’ forms with a smooth surface, and un- 
perforated walls, the distinguishing characteristics of the genus 
being the absence of verrucze and of “tubercules calicinaux,” 
and the possession of entacmzeous tentacles arranged in two 
cycles. The absence of cinclides and acontia would incline one 
to deny any similarity between this genus and Gosse’s Azftasza, 
but, since two at least of the four original species of Dysactis 
are now known to possess these structures, we must consider 
the imperfect knowledge of the forms the cause of the erroneous 
association of species found in the genus. It is to be noticed 
in this connection that the form which Verrill in his earliest 
paper (64) refers to the genus Dysactis is, as I have satisfied 
myself by the examination of specimens, really an Azptasia — 
A. pallida. Subsequently (66), Verrill made this form the 
type of a new genus Paranthea. 
The genus Dysactis must be considered synonymous in part 
with Gosse’s Azftasia, but on account of the imperfection of 
the definition, it seems preferable to disregard its priority and 
to retain the latter name. As stated above, Gosse (’60), though 
recognizing the presence of cinclides and acontia, separated his 
1 In neither of the species described here is there any trace of a circular muscle, 
and the same is the case with 4. diaphana, according to the Hertwigs (’79). I have 
found, however, in 4. pallida a slightly developed muscle imbedded in the mesoglcea. 
