4.06 G. HERBERT FOWLER. 
there is no specimen of the corallum in England, has caused 
one or two points to be left undetermined. I have no record 
of the locality from which the specimen was taken; probably, 
like the other known specimens, it comes from the West 
Indies. 
The corallum consists of a single theca, attached below to 
some foreign body by its side, but curving upwards to the 
vertical. It is covered externally by a thick epitheca, which 
rises some distance above the level of the septa ; the latter are 
generally twenty in number, of which ten are longer than the 
rest. They unite in a pillared columella. 
From some manuscript notes by Professor Moseley it 
appears that, in the retracted condition, the peripheral part of 
the oral disc is drawn inwards and downwards, so as to com- 
pletely cover the tentacles (fig. 1), a condition which is 
characteristic of Actiniaria, but which has been described for 
Sphenotrochus only among Madreporaria (‘ Anat. Madr.,” iv). 
As to the general characteristics, he observes that there are 
“‘twenty pali of two sizes, symmetrically arranged; two of 
the cycle of ten smaller ones occupy the dorsal and ventral 
middle lines, judged from the one-sided attachment of the 
calicle” [that the attachment of the calicle does not indicate 
the true dorso-ventral axis of the polyp, appears from the fact 
that the septa in the entocceles of the directive mesenteries 
belong to the longer cycle]. ‘ Attached side being termed 
dorsal, the interval between the outer ends of the pali and the 
border of the calicle is much greater ventrally than dorsally, 
indeed it almost disappears dorsally. The position of the 
mouth is thus somewhat excentric dorsalwards, and that of the 
cycles of pali correspondingly.” 
The next anatomical character of interest is that there is no 
trace of any soft tissue on the outside of the calicle ; Duncania 
agreeing in this respect with Flabellum (‘ Anat. Madr.,” i). 
1 T am not able to say from personal knowledge that no tissues were present 
on the exterior before decalcification ; but it is very improbable that Professor 
Moseley would have omitted to mention the fact in such a case both in his 
MS. notes and when giving me the sections. 
