140 Colonial Organisms. [ February, 
abundant they are swept through the pharynx and into the body 
in a strong stream, the animal having sufficient intelligence to 
know and to reject what may be unpleasant or non-beneficial. 
With indigo it refuses to have anything to do; and a particle of 
any kind that may be too large, or otherwise unacceptable, 
scarcely passes the oral aperture before the current is reversed 
and the disagreeable substance dashed out. ae afl 
Reproduction with the form referred to as Tillina inflata, n. Sp 
is accomplished, so far as I have observed, by encystment and 
subdivision of the body into four zodids, which differ from the 
adult in no particular, except in their smaller size. 
A’ 
COLONIAL ORGANISMS. 
BY CHARLES MORRIS. 
Ie remarkable resemblance which appears between the sep? 
rate segments of an Annelid, the distinct, units of a m 
zoan, or in the sectional parts of other forms of the animal ; 
vegetable kingdoms, is one that admits of two interpretatio 
and has in consequence given rise to two opposed theories. * 
the first, supported by several eminent scientists, it is a a 
that each unit or segment represents an original individual, i 
that the existing individual arose through the subordin” g 
the members of an original colony. In the second, support di 
equally eminent authorities, it is assumed that the organs í 
-original individual gradually took on the form and in 
the parent body, and thus, though originally diverse in fun 
grew to closely resemble each other. d 
This latter theory, which is based on the assumed tendency 4 
each cell or other portion of an organic form to develop into i 
exact reproduction of that form, is supported by Huxley, . 
Beneden and other biologists. The opposite theory, "ae 
based on the apparently direct indication of the facts, 15° 
by Allman, Gegenbaur, Claus, Lankester, the Hertwigs, ee -divit 
discoveries seem to sustain the colonial rather than the ™ t 
ual theory. The probable fact is, however, that they are q te 
a certain extent, true, and that both the colonizing habit p he 
reproductive power of single cells have had their share ult 
formation of the closely similar sections of Hydrozoat = 
melidan individuals. ` 
