127 
tioned, the general form is often very closely that of the 
seaweed, and the polypide, which was called the flower, is 
not formed until the zooecium* is moderately developed; 
then after the polypide has enjoyed life for a time it dis- 
appears by decay and resorption, and in time another 
polypide buds out from the inside of the same cell, and 
thus it was held that the “flower” was deciduous. Again, a 
very large number throw out radical tubes and fibers. Some 
have a large number at the base, as in Cellaria ceroides, others 
from all parts of the stalk, and from specimens of Diachoris 
I find there is one root from the back of each zooecium 
(cell). That these points were used to maintain their 
animal plant nature, when but little was known of their 
anatomy, cannot be wondered at, and we may see why 
Pallas j* says “Zoophyta esse animalia vere vegetantia, in 
plantse formam excresentia; plantarumque alias quoque 
proprietates aflectantia; esse plantas quasi animatas.” 
The Bryozoa are divided into two orders : (1) the Phylac- 
tolsemata which are fresh water. The tentacular disk is 
horse-shoe shaped and the mouth has an epistome or cover 
which closes it. (2) the Gymnolsemata have the tentacular 
disk circular. These are marine, and as my studies have 
been confined to these I shall only consider them to-night. 
The first suborder, the Cheilostomata represented by 
Flustra, Leprelia, Eschara, &c., is the largest and most im- 
portant. They have an operculum to the aperture of the 
zooecium (cell) while the Cyclostomata have none. These 
last are all calcareous, and the form of the cell is more tubu- 
lar than in the Cheilostomata, and on this character was 
based d’Orbigny’s classification. The best known form is 
Crisia. The Cyclostomata have had much less attention 
than the other divisions. 
* The zooecium is the cell in which is the polypide, consisting of the 
alimentary canal and the tentacles. As the word cell is used for a single 
cell of cellular tissue and for a chamber (as the bee’s cell) it is necessary 
to use the term zooecium for the sake of clearness. 
f Elenchus Zoophytorum, p, 19. 
