Macuire—WNotes on Certain Actiniaria. 719 
filled with a mass of partly broken down acontia. The number 
and arrangement of the mesenteries are almost identical with 
those of the larger specimen. But below the gullet, one of each 
of the two pairs of lateral primary mesenteries leans over towards 
the corresponding adjacent mesentery on the same side (that 
furthest from the directives). Lower down, these mesenteries fuse 
completely, forming a lateral chamber on each side of the animal. 
The primaries and secondaries bear mesenterial filaments and 
acontia. There are no gonads in this specimen. In both specimens, 
‘the muscles have the usual Hexactinian arrangement. The retrac- 
tors are well developed on the primary mesenteries, forming a well- 
marked pennon. The parieto-basilar muscle is fairly developed. 
ETGao 
Phelita Sollas7.—Small specimen, below the cesophagus, showing fusion of lateral 
primary mesenteries. 
Sphincter.—The sphincter extends through about the upper 
third of the body-wall. 
It is mesoglceal, occupying at its commencement the inner rhalf 
of the mesogloea which is here very thick; though the muscle has 
sunk into the mesoglea, it is not sudounied by it, but is still 
directly continuous with the endoderm, where the body-wall is thick. 
Higher up where the wall is thinner, the muscle is much reduced, 
only a few strands, which are separated from the endoderm, being 
visible. There is a stronger portion forming a small prominence in 
the body-wall at the base of the outer tentacles ; here the muscle 
_ occupies almost the whole thickness of the mesoglea, but the lower 
part, where the body-wall is thick, is much the best developed. 
The endodermal circular muscle persists inside the sphincter. 
