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ANEMONE FOSSIL SPONGE 
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ZOOLOGY. 23 
beings. If, now, Spontaneous Generation does not take . 
place, the Monera and Amcebe of the present day, and the 
other orders of the Intermediate Kingdom also, are the 
posterity of the long dead original forms, the ancestors of 
the three kingdoms,—the animal, the vegetal, and the 
intermediate world. (See Tree L, page 24.) 
SPONGES. 
The sponge of every-day use (Figs. 11, 12) is composed 
of a horny, fibrous material, produced by a colony of 
Ameebe, and if a section of the fresh-water Sponge 
(Spongilla) be made, a glance will explain by what means 
the currents of water are produced, which can be seen 
under the microscope. The outer layer is composed of a 
number of Amcebe, with little openings, through which 
the water enters the cavity between the outer and inner 
layers, this inner layer being also composed of Amcebe, 
in the deep substance of which are chambers lined with 
fine hairs (cilia), whjch, working in the same direction, force 
the water through them into a common outlet; in this 
manner strong currents of water pass in and out of the 
sponge, making a little whirlpool, into which minute par- 
ticles of matter are dragged. 
Sponges are found attached to all kinds of rocks, and 
often to shells, both in the sea and on the beach, and are of 
two kinds, soft and hard, of which the soft are probably the 
ancestors of the hard. The Halisarca, or Slimy Sponge, is 
found attached to the leathery sea-weed, and is composed 
of slimy Amoeba-like bodies, in which the canal system 
just described is only imperfectly developed. From this 
kind were derived the Gummy Sponges, so called from their 
gumlike consistency; their canal system foreshadows the 
homologous structure in thre Jelly-fish. Sponges like the 
Halisarca were probably the ancestors of the first kind of 
