Note 455 — Chapter IX · ON CONCRETIONS, SPICULES, AND SPICULAR SKELETONS
Reading edition
In an anomalous and very remarkable Australian sponge, just described by Professor Dendy (Nature, May 18, 1916, p. 253) under the name of Collosclerophora, the spicules are “gelatinous,” consisting of a gel of colloid silica with a high percentage of water. It is not stated whether an organic colloid is present together with the silica. These gelatinous spicules arise as exudations on the outer surface of cells, and come to lie in intercellular spaces or vesicles.