to an entirely shut canal, which is free from the mesentery in its upper part (PI. VI, fig. 12). 
The testes are enclosed in mesogloeal capsules. Almost all the testes are unripe and contain 
spematocytes; in one single place only there are ripe spermatozoa in part ot one of the 
mesenteries. They are like those in Eucirripathes Rump 1 in. 
Parasites. Symbiotic Algae are rather abundant in the entoderm of the tentacles, the 
actinopharynx and other parts, but also in the actinopharyngeal ectoderm, though less abundant. 
The polyps of a -second colony differ from the preceding colony in the strikingly swollen 
mesogloea : it is obvious that this thickness varies to a very high degree through preservation. 
Ectoderm and entoderm have disappeared for the greater part; they are relatively thin, com¬ 
pared with the mesogloea. The mesogloea is homogeneous with rare traces of fibrillae. The 
thickness is at the tentacular base 2 80 p, and over!; in the oral cone and in the bodywall 100 p; 
in the actinopharynx a- 15 p; in the mesenteries 20 p. The lumen is rather small; the ten¬ 
tacular lumen is only slightly more than the mesogloeal thickness. The shape of the actino¬ 
pharynx is rather curious; in one polyp it is sagittally elongated and in the neighbouring polyp 
transversally elongated. — The mesenterial muscle-system is quite the same as in the other 
colony, but no musclefibres are to be found on the sagittal mesenteries. The mesogloeal 
lamellae are basally fused, in groups. 
26. Stichopathes sacctila sp. n. (PI. VI, fig. 13; PI. VII, fig. 2). 
Tentacles. The ectoderm (70 p) has nematocyst-batteries, surrounded by a small 
number of deeply staining glandcells. The nervous layer is at a normal depth. There are very 
slightly developed longitudinal musclefibres. The mesogloea (8 p) is a homogeneous layer 
with very rare fibrillae and with circular ridges on the entodermal side. The entoderm (55 p) 
does not contain any deeply staining glandcells, but only hyaline ones. A nervous layer is not 
to be seen, but there are circular musclefibres. 
Bodywall. The ectoderm (40 p) is the same as in the tentacles, but there are no 
nematocysts, while the number of deeply staining glandcells is large. There are very slightly 
developed musclefibres, but their direction is not to be made out. The mesogloea (8 p„) and 
the entoderm (40 p) are both the same as in the tentacles. The oral cone has a wall of 
the same thickness, but there are no deeply staining glandcells in the ectoderm. There are 
circular musclefibres in the entoderm; even the entodermal side of the mesogloea has small 
lamellae for these musclefibres. There is an interzooidal septum with some slightly 
developed secondary septa, which consist of mesogloea only, while the entoderm of the 
bodywall does not follow these mesogloeal irregularities, but covers them with a smooth 
surface as in PI. Ill, fig. 2. — There is a basal septum like that of PI. V, fig. 6, but 
it is complete over the entire breadth of the polyp. It is fixed to the lower border of the 
primary transversal mesenteries, which border is free in other species. This septum is easily 
to be distinguished from the axis-layers, since the basal septum entirely merges into the body- 
wall at the poly par limits. 
The Axis-layers are lost for the greater part of them; ectoderm and mesogloea are 
