262 THE MIcROSCOPE. 
They are all oval or subcircular in outline, and very much’ 
flattened, while some are bordered by one or two rows of doubly’ 
barbed hooks, whose purpose, I imagine, may be to prevent the 
statoblast from being swept away by the currents, since the 
hooks form most effectual anchors. These marginal spines or 
double hooks are visible with a good pocket-lens, but on the 
majority there is a structure demanding the compound instru- 
ment for its elucidation. This is the annulus, a dark brown 
ring encircling the statoblast and composed of innumerable 
hexagonal cells. It occurs on all known forms except on those: 
of a single genus, F’redericella, where the winter eggs are entirely 
smooth. There are, however, three genera which are not known. 
to produce statoblasts, two foreign, Norodonia, from Siam and. 
Fig. 5--Pectinatella statoblast. Fig. 6—Cristatella statoblast. front view. Fig. 7— 
Cristatella statoblast, side qiew. A—Annulus, 
China, and J/islopia, from central India, with the Urnatella of our 
own country. The latter is supposed to reproduce itself Py 
means of the urn-shaped segments of the stem. 
Within the body of each Polyzoan there is a cord-like struct~ 
ure extending from the lower end of the stomach to the bottom 
of the cell-like posterior part of the animal. This is named the 
funiculus, and from it the statoblasts are formed by a process of 
budding. “They arise,” says Professor Alpheus Hyatt, “ within 
bud-like swellings of the funiculus, and, enlarging, slowly push 
out to the surface of the cord, and upwards toward the stomach,. 
until finally they hang upon the exterior, arranged alternately on 
either side, the youngest being at the lower end.” 
Each Polyzoan seems capable of producing only a limited 
number, yet the Polyzoa forming even a single colony are so 
numerous that the number produced is in the aggregate someé 
thing astonishing. re 
