550 
DE. CAEPEXTEE’S EESEAECHES OX THE EOEA^imTEEA. 
These spines are usually few in young specimens, and become numerous with age ; but 
this rule is by no means constant, since full-grown specimens are occasionally met with 
having no more than four or five very short spines (Fig. III. h). The spines are usually 
either cylindrical or somewhat club-shaped, the latter form being the more common; 
but we occasionally see them showing a tendency to bifurcation at their extremities ; 
and they not unfrequently appear as if two, three, or even four spines had coalesced to 
form one, — this being indicated not only by its unusual size, but by the mutual divergence 
of its components as they extend themselves from the central disk (Fig. I.b, and Fig. II. f). 
A somewhat remarkable contrast in the relative 
development of the disk and of the spines is pre- 
sented by the general aggregate of the Philippine 
and Mediterranean specimens placed in my hands 
by Mr. Cuming ; as is shown in comparing Figs. II. 
and III. It is in the former (Fig. II.) that we meet 
with the greatest number as well as the greatest 
relative length of the spines ; and that the bifurca- 
tion or trifurcation of their extremities presents itself. 
In full-grown specimens of the Philippine Calcarina, 
we commonly find the spines diverging from the 
rig. I. 
Tvo specimens of Philippine rariety 
of CaJcarina, distinguished by unusual 
exuberance of spinous outgrowths. 
OutUne-representations of various specimens 
of Philippine variety of Calcarina. 
G H 
Outline-representations of various specimens of 
IMaltese vai’iety of Calcarina. 
