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ectoderm. There are other, less deeply staining glandcells of a larger type, and some small 
hyaline ones also. The peripheric layer shows its small glandcells best in tangential sections. 
The nervous layer is well developed, separated from the mesogloea by an open space; the 
nuclei of this layer are the same as those at a higher level. — The mesogloea is thin, 
homogeneous, and thickened in the places where the mesenteries are attached to it (PI. V, fig. i8)- 
The entoderm (PI. I, fig. 19) is the same as in the bodywall, but more loosely built, perhaps 
through the presence of numerous hyaline glandcells. The actinopharyngeal ectoderm is continued 
lip-wise outside the mouth (PI. V, fig. 17) while this lip is easily to be distinguished from the 
actinopharynx by the presence of a limiting groove in the ectoderm and by a mesogloeal 
lamella between both parts of the ectoderm. The entire oral cone is oblique; in its lower part 
the actinopharynx descends to the deepest level along the primary transversal mesenteries. The 
ectoderm is folded deeply, in correspondence with the places of attachment of the mesenteries 
(PI. V, fig. 18), 
The mesenteries have a regular course and structure. The mesogloea is thin and although 
there are no musclefibres, both' sides of the mesenteries are inclined to show a difference of 
thickness of the entoderm. — There are no ovaria or testes. 
Mesenterial filaments are to be found along the primary transversal mesenteries only 
(PI. I, fig. 18; PI. V, figs. 18 and 20). At first they are unbranched (fig. 20), but at a greater 
distance from the actinopharynx they become branched. They are single-lobed with actino¬ 
pharyngeal ectodermal structure. The mesenterial mesogloea is narrowed before branching into 
a fork. The very numerous nuclei form a zone which is clearly limited from the rest of the 
filament, and which has a somewhat smaller number of nuclei in its periphery. There are some 
hyaline glandcells together with the small deeply staining peripherical glandcells. I thought I 
saw some nematocysts in the distal part, but I could get no certainty about this point. There is 
a nervous layer in the deeper part of the epithelial layer. — There is a great number of yel¬ 
lowish pigment granulae in the nuclear zone, the same as are found in some lower parts of 
the actinopharynx. 
3. Eticirripathes trcinslucens v. Pesch. 
Tentacles (PI. II, figs. 1, 3 and 9). The ectoderm (75 — 105 p.) is very thick when 
compared with the bodywall, as is also the case with the other layers. Almost the entire upper 
half of the ectoderm is filled with deeply staining glandcells. In some places they surround 
nematocyst-batteries (PI. II, fig. 1). There is a large accumulation of nuclei below these batteries. 
The nervous layer is well separated from the mesogloea and there are very slightly developed 
longitudinal musclefibres, lying against the mesogloea. The mesogloea varies from 140 p. at 
the tentacular base to 10 p. at the top of the tentacle. Where two lateral tentacles touch each 
other at the base, a thickness of 500 p. may be met with. — It is a homogeneous layer. 
Sometimes there is a fibrillar division of the mesogloea; these fibres connect ectoderm and 
entoderm and the bundles are more branched at the ectodermal side than at the entodermal 
side (PI. II, fig. 9). However it is not impossible that we have an artefact here through the 
