182 
ate with the endoderm through an aperture in the mesogloea. Some- 
times 1 observed an invagination of the endoderm towards t e 
aperture for the testes. The structure of this formation recalls the 
so called thread-apparatus (“Nahrapparat", O. u. R. Hertwig: le 
Actinien, Jena 1879), the nature of which I will discuss tn another 
paper. To my mind this “nutrition" apparatus may m the hrst 
hånd be interpreted as a preformed aperture of the reproductive 
organ. . 
The mesogloeal off-shoots in the most aboral part of the acti- 
nopharynx are strong. At least 6 mesenteries are attached to the 
broad siphonoglyph (fig. 7 si). The ectoderm of the s.phonoglyph 
contains few giand cells except in the region bordenng on the other 
parts of the actinopharynx. 
1 have not identified the species described above with any of 
the East Asiatic species: Cerianthus orienialis, Cerianthus Stimpsomi 
(Verrill: Synopsis Polyps and Corals North Pacific Explor. Exp. Proc. 
Essex Inst. 4, 5 1865, 1866—68. Wassilieff: Japanische Actmien, 
Abh. K. Bayer. Acad. 1. Suppib. 1898) and Pachycerianthus benedeni 
(Roule: Compte Rendus Acad. Sc. Paris 138. 1904). The descrip- 
tion of these species is namely so imperfect and, concerning the 
two first only based on external characters, that it is quite impos- 
sible to identify them. In the supplement of the Challenger Ac- 
tinarians (Challenger Report Zool. 73 1888 p. 54) R. Hertwig States 
that Cerianthus membranaceus was dredged at the Phihppme Islands. 
That is certainly incorrect. The specimens are more probably ident- 
ical with C- mortensenii. 
4. Pachycerianthus plicatus n. sp. 
Diagn osis: A large species with much more than 100 tent- 
acles. Marginal and labial tentacles long, the latter thin. Arrange¬ 
ment of the marginal tentacles 2 (dt) 431 | 4231 | 4231 | .. 
and of the labial tentacles 3 (dt) 413 ] 4232 | 4312 | . Direc 
tive labial tentacle present. Actinopharynx comparatively short, 
12 mesenteries attached to the broad siphonoglyph. Hyposulcus short, 
hemisulci rather long, filamentous, without ciliated tract. Directive 
mesenteries shorter than p 2 . P 2 mesenteries short, about of the 
same length as m 2 with a well developed ciliated tract, a bunch 
of craspedonemes of the ciliated tract and a small cnido-glandular 
