BARBADOS-ANTIGUA REPORTS 43 
With a few exceptions the Polycheta are unisexual. The 
sexual cells are developed in all cases from the lining epithelium 
of the body-cavity. The exact spot where this occurs varies in 
different cases. The eggs and spermatozoa in the Polycheta are 
discharged into the sea either by rupture of the body wall or 
through the nephridial pore. The male and female elements 
unite, after which the fertilized eggs undergo development in 
one of three ways: (1) free-floating; (2) embedded in jelly; 
or (3) attached to the body or to the tube of the worm. The 
larval forms differ greatly from the adults. The free-swim- 
ming larva is known as a ‘‘Trochosphere.’’ In different species, 
however, the larva present various departures from this type. 
The little animal is equipped for an independent life by means 
of provisional chetze which help to keep it balanced. It is 
quite at the mercy of the sea, which disseminates the species 
by carrying it hither and thither. The larve of certain species 
occur at definite periods in great numbers at the surface of 
the sea, where they serve as food for other animals. 
A peculiar worm, Palolo viridis, is used as food for man. 
This worm spawns on two days in October and on two in No- 
vember—the day on which the moon is in her last quarter, and 
the day before. At these times they leave the reefs and come 
to shore. The natives of Samoa and Fiji eat these alive or 
baked, tied up in leaves. They consider these so great a delicacy 
that the chiefs who live on the shore send them as gifts to those 
living inland. 
A few Polycheta are pelagic, while the majority live on the 
sea-bottom. They occur in the greatest abundance near the 
shore; but they are also found at all depths in the ocean, where 
the tube-dwelling forms‘are more abundant than the {free 
forms. A considerable number are commensals, habitually 
associating with other animals for the sake of food and shelter. 
Tubes and horny jaws of various Polycheta have been detected 
in the strata from the Cambrian period onwards. 
The geographical distribution of these worms is wide-spread. 
Many genera are cosmopolitan, although only a few species are 
common to all the great oceans. 
