The genus Aulosphæra, the first observed form of all Aulosphærida, is also the most common form of the whole family, the richest in distinct species, and widely distributed over all oceans, in the tropical as well as in the temperate and Arctic zones.
The twenty-one species here enumerated may be only a small part of the numerous forms, which may be distinguished according to the different forms of the tubes. One of the two Mediterranean species, which I first described in my Monograph, is cosmopolitan. The shell is in all species a simple regular lattice-sphere with triangular meshes; it differs from the preceding Aularia in the development of radial tubes at the nodal points of the lattice-work.
Subgenus 1. Aulosphærantha, Haeckel.
Definition.—Radial tubes simple, smooth, without terminal teeth and without lateral branches.
1. Aulosphæra trigonopa, Haeckel.
Aulosphæra trigonopa, Haeckel, 1862, Monogr. d. Radiol., p. 359, Taf. x. fig. 4.
Radial tubes of the spherical shell cylindro-conical, straight, smooth, of the same length as the tangential tubes of the network, which are also smooth, straight, cylindrical.
Dimensions.—Diameter of the sphere 1.0 to 2.0; tangential tubes 0.1 to 0.2 long, 0.002 to 0.004 broad.
Habitat.—Cosmopolitan; Mediterranean, Atlantic, Indian, Pacific, surface.
2. Aulosphæra flexuosa, n. sp.