112 THE VOYAGE OF H.M.S. CHALLENGER. 
which in their turn have also given rise to smaller ones. The parent calicle is circular, and 
attains a very large size, apparently being more than 6 em. in diameter, before the develop- 
ment of buds takes place around it ; and by the encroaching of the smaller calicles upon its 
surface, it becomes at the same time both polygonal in shape and smaller in size. A very 
curious feature is that the parent calicle of the colony has grown out of, and immediately 
above, another large similar calicle which was simple and which produced no marginal buds 
to form a colony. It seems to be a simple case of rejuvenescence, although the border of 
the lower calicle projects for some little distance on one side beyond and outside of the base 
of the upper one. It is easily understood that, if the same conditions had prevailed 
during the growth of the second upper calicle, and throughout successive generations, as 
had prevailed during the life of the dead lower one, instead of forming a convex colonial 
mass, the whole colony would have assumed the appearance of an elongated cylinder 
made up of successive superposed calicles, as in the simple species of Cyathophyllum. 
A veryyoung stage of the species is seen on the projecting portion of the dead lower 
ealicle, where a small calicle has budded off. In this small cup three large and thick 
septa are distinctly seen, arranged like three arms of a Maltese cross, while the fourth 
arm is but slightly, though distinctly, larger than the septa around it. Though thus 
pointing to a distinct tetrameral arrangement of the septa, it seems to me, however, to 
be more likely a case of accidental growth, since no clear evidence of tetrameral arrange- 
ment can be found in the other calicles of the colony. 
The tabul of this form are peculiar, and present rather closely the shape found in 
Strombodes. Looked at from below, they are seen to be sub-infundibuliform, the septa 
being prolonged to meet at the centre. At this point, and for some distance around it, 
the obliquely placed dissepiments coalesce to form a nearly solid, dense plate in which the 
septa can be distinguished. 
Though differmg from the most completely formed tabulee, as seen in Amplexus, 
by this distinctness of the septa, the tabule of Moseleya latistellata present all the funda- 
mental features of those characteristic of many of the Cyathophylhde, in several of which 
also the septa are distinguishable. The tabulee are placed regularly one above the other, 
with vesicular endotheca between them, as can easily be shown by removing the basal 
pointed part of the lower one, when the interior one is laid bare. They apparently 
correspond with the basal part of the new calicles, which are formed, probably, by 
rejuvenescence above the previously existing one; and in transverse section are seen as 
concentric circles of more or less variable thickness and regularity. 
A transverse section, across the parent calicle, has been made of the single 
specimen obtained; but, owing to the small size and the thinness of the remaining 
parts, a vertical section would have been of no practical use, and was not attempted. 
The shape and nature of the tabule and their relation to each other, however, 
can be easily demonstrated by the views of the basal part of the corallum, where 
