2 I 2 
by a folding of the axis-wall. Near the top of the colonies the axial layers are for the greater 
part fused with the bodywall so that the gastral cavity is nearly absent. — The oral cone is 
a double funnel with a very wide mouth and a distinct lip in one of the colonies, but in the 
other one it is dome-shaped with a small mouth, as in the normal type. In one colony there 
is a brownish green pigment in the actinopharyngeal ectoderm but only in the lowest part. The 
mesenterial filaments, very slightly developed along the sagittal mesenteries, are branched and 
convoluted (as to fill the greater part of the gastral cavity and the basal half of the tentacular 
lumen) along the transversal ones in one colony, but very slightly developed in the other colony. 
They are kidney-shaped in section, with a very abundant pigmentation. This pigment is not quite 
the same as in other species; it gives the impression of being of nutrimental origin since the 
same material is found as an amorphous mass in the gastral cavity, the actinopharynx and 
even in the mouth; for sure it is worthy of note that it is entirely absent in the other colony. — 
Along the primary transversal mesenteries, but not along the other ones, there are muscular 
fibres to be found with small mesogloeal lamellae, but only in a very undeveloped condition. 
The specimen of station 64 has a tentacular ectoderm, which is very rich in deeply 
staining, homogeneous glandcells, while they are entirely absent in the ectoderm of the tentacles; 
the same holds good for the bodywall and the oral cone. The spines are club-shaped with a 
thin stem. The mesenterial filaments are found only along the primary transversal mesenteries. 
The specimens of stations 193, '213 and 313 have some longitudinal musclefibres in the 
tentacular ectoderm, while the nervous layer is separated by an interval from the mesogloea. 
The ectodermal origin of the axis can be examined in the cross-sections through the apex of 
this colony. At the top itself there is only a cylinder to be seen of ectoderm, mesogloea and 
entoderm; the ectoderm has many glandcells. But at a distance of 9 p from the top there is a 
small ectodermal massive invagination in the mesogloea; in the following- sections this invagination 
contains the axis as an intricate mass of epithelial cells and horny matter. In other sections, 
still further from the top, these cells arrange themselves into a high cylindrical epithelium, at 
first irregular in thickness, with an irregular axis, but furtheron with a uniform thickness and 
a round axis, which by now is yellow, while at first it was colourless. The ectoderm is 33 p, 
the mesogloea less than 1 p, the entoderm 7 — 14 p (normally: resp. 5 — 8, less than 1, and 
5 p). At first the connecting septum is a very broad fusion between the bodywall and the axial 
sheath, but soon the septum diminishes to a very short and narrow strip. — The actinopharynx 
broadens as in the general type, but it is constricted at a certain depth before it broadens 
again to a still greater extent. The mesenterial filaments are only to be found along the trans¬ 
versal mesenteries and they are unbranched and only slightly convoluted. 
The specimen of station 257 has some nematocyst-batteries in the ectoderm of its body- 
wall. The existence of an interzooidal septum is dubious. While the ectoderm of the oral cone 
is rather sparingly provided with deeply staining glandcells, these cells (not of the actinopha¬ 
ryngeal type) are very profuse in the interior of the mouth and the neighbourhood of the mouth. 
There are no musclefibres in the mesenteries but in the primary transversal mesenteries one 
side of the mesogloea is somewhat swollen. The mesenterial filaments along these mesenteries 
are branched. In the mesenterial filaments, which are circular in section, the mesooloea of the 
