60 Rev, T. R. R. Stebhing — On Calceola sandalina. 



The Zoantharia rugosa so often mentioned are invested with a 

 wrinkled sheath or outside coating called the epitheca. Such a 

 coating appertains to Calceola sandaltna. In this, as in so many 

 other species, the epitheca exhibits the lines of growth encircling the 

 calyx. When the nap, so to speak, is worn off this outer garment, 

 a threadbare appearance is presented, the lines running from the 

 mouth of the calyx to the apex, representing, not the sculpture of a 

 Brachiopod shell, but the outer edges of the septa, just as they are 

 seen under similar circumstances in many of the allied genera. 

 These septa are no mere surface-markings. A section made at 

 about ^ of an inch from the mouth of a large calyx, and parallel to 

 it, shows them plainly in the interior, numbering about 160, or 

 perhaps they are 80 with two laminte apiece. 



The Zoantharia rugosa are distinguished by a quadripartite arrange- 

 ment of the septa. Such an arrangement is visible in Calceola 

 sandalina. The section just described shows four depressions, two 

 at the angles where the curve meets the flattened side, one in the 

 centre of the curve, and the fourth in the centre of the flattened side. 



The Zoantharia rugosa exhibit in many genera a structure as if 

 many funnel or basin-shaped layers were packed inside one another. 

 It is found very conspicuously in Chonophyllum, but also in 

 Goniophyllum, in Cyatliopliyllum, in OmpJiyma, in Stromhodes, and 

 moreover in Cystiphyllum. It does not fail us in Calceola sandalina, 

 the only difference being that there it is more neat and regular than 

 in the other forms. 



Looking now into the hollow of the calyx and to the inner surface 

 of the operculum, we shall not only not find any traces of muscular 

 impressions such as appear in Brachiopod shells, but we shall find 

 that none such could ever have existed, for the whole of the inner 

 surface of both calyx and operculum is seen, in the best-preserved 

 specimens, to be occupied by the elevated edges of septa, or what in 

 the operculum are the equivalents of septa. 



A peculiarity not noticed by Lindstrom is that a small process 

 rises up from the bottom of the cavity like a false columella. It 

 would also appear, contrary to his supposition, that a depression 

 actually exists in the centre of the flattened side, as before mentioned, 

 although in perfect specimens a sort of plate or staple, consisting of 

 two laminae, takes the place of the depression in the upper part of 

 the calyx. 



The operculum is semicircular, coated with an epitheca showing 

 numerous concentric lines of growth. Like the calyx, it has a 

 flattened side, in form a very obtuse-angled equilateral triangle, with 

 the hinge-line for its base. Its inner surface exhibits numerous 

 septiform rays, which start from the hinge-line and reach the circum- 

 ference, having a pinnate arrangement on either side of a large 

 central ridge. The ridge itself is separated from the hinge-line by 

 a pit or depression, which fits the top of the staple-like process in the 

 calyx. The rays are prominent at the rim of the semicircle ; 

 along the hinge-line they seem to serve the purpose of minute hinge- 

 teeth, projecting more or less alternately, one on either side of the 



