CORAL. iE 
construction. The polygams have their flowers of a masculine, 
feminine, and neuter gender. 
The coral polype is viviparous—that is, the eggs become 
embryos before they leave the parent. The eggs have long 
slender pedicles; they come out of the thin layers which line the 
digestive bag; they are spherical, opaque, and of a milk-white 
colour. They detach themselves by breaking their pedicles, 
and thus fall into the central cavity of the polype, a cavity which 
serves at once as a stomach and an incubating pouch. Here two 
very different processes are in action—the one dissolving the food 
and nourishing the animal, the other developing and producing a 
new creature. In due time, the eggs lengthen and vibratile cils 
appear. As soon as they are born—that is, vomited—a pore opens 
at one of the extremities, which is destined to become the mouth. 
Then they assume the form of a whitish, semi-transparent worm. 
These larve swim in all directions with the greatest agility ; they 
rise and sink in the vases which contain them, always swimming 
with their thicker extremity in advance, carrying their mouths in 
the rear, so that they butt against anything which happens to be 
in their way. They have a tendency to become fixed, like their 
parents, and the mode of their progression greatly favours this 
result ; thus the peculiarity of their motion is liable to shorten 
the period of their liberty in facilitating their adherence to any 
object with which they come into contact, by that part of their 
body which afterwards becomes the base of the polype. 
When it adheres, the polype has reached another phase of its 
existence. As soon as it becomes fixed it changes its worm-like 
appearance, and thickens, gaining in breadth what it loses in length, 
thus shortening and becoming discoid. The thin extremity which 
carries the mouth gradually folds itself back by the successive stages 
represented in figs. 5, 6, 7, 8 (Plate VI.), until the larva assumes 
the shape of a pin-cushion (fig. 9), at the summit of which is the 
mouth. Around this orifice the rudiments of the eight tentacule 
begin to appear, which soon cover it with a pendant festoon (fig. 10). 
The fixed larva thus becomes the founder of a large colony. Buds 
form on the axis, and develop themselves into a whole nation of 
corals. 
The young polypes just hatched from the egg are, as we have 
