58 MCMURRICH. Vor. ULE: 
The fronds, situated on the periphery of the disc, are in a 
single cycle, one surmounting each longitudinal row of verrucz, 
there being altogether apparently 24, corresponding thus to the 
intramesenterial spaces. In structure they are irregularly lobed 
thickenings of the disc, the mesogloea being thrown into nume- 
rous folds, and here and there thickened so as to form slight 
wart-like prominences. They lack the folded muscular layer 
which is to be found in the disc and in the inner tentacles. 
These are situated near the mouth, a naked area of the disc 
being left between them and the fronds. I am not quite certain 
as to the number of these inner tentacles; I counted 42, but 
probably the number should be 48, one corresponding to each 
intermesenterial, and one to each intramesenterial space, or else 
two to each intramesenterial space, their arrangement not having 
been made out. They are cylindrical in shape, tapering towards 
the extremity. Their longitudinal musculature is strong (PI. IV., 
Fig. 13, mp), the mesogloea being thrown into numerous ridges, 
over which the muscle cells are arranged. 
The disc is structurally like the inner tentacles. The mouth 
I could not see, the tentacles completely covering it, but pre- 
sumably the gonidial angles are well marked. In transverse 
sections through the stomodzum the two gonidial folds are 
well seen. They extend downwards for some distance, forming 
two strong languettes (Pl. IV., Fig. 14). Their structure differs 
noticeably from that of the rest of the stomodzeum, the meso- 
gloea being much thickened, the ectoderm much higher than 
elsewhere, and the nerve layer very distinct. They approach 
much nearer the column wall than the stomodzum elsewhere 
does, the gonidial groove being very deep. 
The pairs of mesenteries are 24 in number, and _ probably 
represent ‘three’ cycles, the formula for which 4s, 6, 16, ‘12. 
All are perfect. Owing to the depth of the gonidial groove 
the directives are much shorter than the other mesenteries. 
In all the muscular layers are exceedingly well developed. The 
inner mesenterial stomata are present, and the mesenteries of 
the third cycle only appear to be gonophoric. The specimens 
examined had only male organs. 
