Ernst Haeckel,
Report on the Radiolaria Collected by H.M.S. Challenger During the Years 1873-1876…
“ In the centre is visible the large, spheroidal, tripylean central capsule, with its three openings, containing a large nucleus with numerous nucleoli. Its oral half is covered with the dark phæodium. The voluminous spherical calymma contains numerous globular alveoles and its surface is covered with scattered, stirrup-shaped pieces of the skeleton. Numerous free pseudopodia arise from the surface. ”
