Most of these radiolarian marls appear to date from the middle Tertiary (Miocene) period, and to be deep-sea formations.
In several cases the character of the radiolarian fauna at different depths presented characteristic differences.
A larger number of new forms has been found in the radiolarian ooze collected by the Challenger, and others fossil in Barbados.
True pigment-cells, belonging to the radiolarian organism, do not occur within the central capsule.
This remarkable species is the oldest known skeleton of a radiolarian, a figure of it being given in 1838, loc.
The whole number of radiolarian genera distinguished in that first system was forty-four.
We unite here all these skeletonless radiolarian colonies into one single genus Collozoum, constituted in my Monograph (p. 522).
Hence it may be supposed that a large part of the red clay consists of decomposed radiolarian ooze.
He found also the shells in the radiolarian ooze of the deep sea.
To him a radiolarian, or any other creature, is of interest, not so much on its own account as for its associations.
Any of various marine protozoans of the group Radiolaria, having rigid skeletons usually made of silica. The skeletons are usually spherically symmetrical and structurally complex, containing elaborate patterns of perforations (through which pseudopods extend) and often spicules. Skeletal remains of radiolarians sink to form ooze on the ocean floor, and prehistoric radiolarian ooze has fossilized to become chert and flint.