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REPORT ON BOTANY, MDCCCXLI : 
not be found sufficient ; but we must agree with him in the 
principal matter, for this reason, that these substances are 
deficient in a central organ, the stomach, which is peculiar to 
all animals. Spongilla is not secreted from an animal 
substance, as the stems of the Sertularia, and similar 
zoophytes, which I acknowledge now to belong to the animal 
world, although I formerly believed they were plants. It is 
not, however, at all credible, that a variety of movements, such 
as the author observed in the germ-like bodies of the Span- 
gilla, should originate from endosmose and exosmose; the 
membranes by which endosmose and exosmose take place 
remain immoveable, for the very reason, that the current of 
the fluids goes through them. Endosmose and exosmose can 
only be employed as an analogy for the explanation, and not 
as an explanation itself, for the simple reason, that they have 
not yet themselves been explained. 
Several observations have been published by Laurent on the 
same subject, i. e., on the Spongillce and their Propagation, 
in the Comptes Rendus of 1840, vol. ii. p. 478, 694, 1050. 
M. Laurent assumes the animal nature of this organization. 
They exhibit, according to him, a three-fold mode of propaga- 
tion : — 1st, Germ-like bodies, which he considers as unciliated 
(non cilies) buds : 2d, Egg-shaped bodies, which are formed in 
the spring, and are different from the egg-formed bodies of the 
later season : 3d, Protean bodies, which liberate themselves 
from the rhizopodal prolongations of the young Spongillce. 
He also speaks of propagation by self- division (scissiparite 
naturelle) of the old Spongillce, M. Laurent, in the second 
memoir, goes through the various phases of life of these 
Spongillce. The first phase is that of latent life, in which 
the egg-shaped bodies and gems are first found ; the contents 
of the former are then globular-watery (globulino-aqueux), 
and at the period of the latent life of the latter, the whole 
Spongilla is still in this state (globulino-aqueux). The small 
projections are still wanting at this time. The second phase 
is that of the embryonic state, when the whole tissue is almost 
siibglobular- glutinous (subglobulo-glutineux) ; the eggs are 
transformed from the globular-watery state into the globular- 
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