CORALLINES. 
131 
folds, radiating round a central pore, which presents a star-like 
appearance. This pore as it opens gives to the polypes the op- 
portunity of coming out. Its 
et %e presents a reddish calyx, 
like the rest of the bark, the 
festooned throat of which pre- 
sents eight dentations. 
The polype itself (Fig. 48) is 
formed of a whitish membra- 
nous tube nearly cylindrical, 
having an upper disk, surrounded 
oy its eight tentacula. bearing 
many delicate fibres spreading 
out laterally. This assemblage 
°i tentacula resembles the corolla 
°f some flowers ; its form is very 
variable, hut always truly elegant. 
. ig. 49 (which IS borrowed Fig. 48. Three Polypes of t.he Coral, 
from M. Lacaze-Duthiers’ great 
Work) represents one of these forms of the polypier. 
The arms of the polype are at times subject to violent agitation : the 
tentacula become much excited. 
If this excitement continues, the 
tentacula can lie seen to fold and 
^>11 themselves up as shown in 
ig. 50. If we look at the ex- 
panded disk, we see that the 
eight tentacula attach themselves 
to the body, describing a space 
perfectly circular, in the middle 
°f which rises a small mammal, 
the summit of which is occupied 
fry a small slit like two rounded 
lips. This is the mouth of the 
polypes, the form being very va- 
riable, but well represented hi 
Tig. 50, where the organ under 
consideration is displayed. 
Fig. in. Coral Polype. (Lacaw- Hut biers.) 
K 2 
