I. Subfamily Aularida. Meshes of the network triangular, regular or subregular. Six tangential tubes united at each nodal point of the net. | ||||||
| Shell spherical, with a simple network. | ||||||
| Without radial tubes, | ||||||
| 682. Aularia. | ||||||
| With radial tubes in the nodes of the net, | ||||||
| 683. Aulosphæra. | ||||||
| Shell spherical, with pyramidal elevations or with spongy framework. | ||||||
| Shell covered with pyramidal elevations, the top of which bears a radial tube, | ||||||
| 684. Auloscena. | ||||||
| Shell with spongy framework, the surface of which bears radial tubes, | ||||||
| 685. Auloplegma. | ||||||
| Shell not spherical, either lenticular or spindle-shaped, with simple network. | ||||||
| Shell lenticular, with shortened main axis and radial tubes, | ||||||
| 686. Aulophacus. | ||||||
| Shell spindle-shaped, with prolonged main axis and radial tubes, | ||||||
| 687. Aulatractus. | ||||||
II. Subfamily Aulonida. Meshes of the network polygonal, usually irregular. Three or four (rarely more) tangential tubes united at each nodal point. | ||||||
| Shell spherical, with a simple network. | ||||||
| Without radial tubes, | ||||||
| 688. Aulonia. | ||||||
| With radial tubes in the nodes of the net, | ||||||
| 689. Aulastrum. | ||||||
| Shell spherical, with a spongy framework. | ||||||
| Without radial tubes, | ||||||
| 690. Aulodictyum. | ||||||
Subfamily 1. Aularida, Haeckel.
Definition.—Network of the shell with triangular, regular or subregular meshes; six tangential tubes being united at each nodal point.
Genus 682. Aularia,[[301]] n. gen.
Definition.—Aulosphærida with triangular meshes in the network, the tangential tubes of which form a simple smooth lattice-sphere. No radial tubes at the nodal points.
The genus Aularia is the simplest form of the subfamily Aularida, or of those Aulosphærida in which the network of the shell is composed of regular or subregular triangular meshes; they are the main group of the family, much more common and far richer in distinct forms than the Aulonida (or the Aulosphærida with polygonal meshes). The shell of Aularia, the probable ancestral form of the family, is a simple lattice-sphere with smooth surface, and differs from the common Aulosphæra in the absence of radial tubes, arising at the nodal points.
1. Aularia ternaria, n. sp. (Pl. [111], fig. 2).
Tangential tubes of the network cylindrical, straight, smooth, of equal breadth. Triangular meshes of the reticular sphere very regular, equilateral triangular. This species is the simplest of all Aulosphærida and similar to the common Aulosphæra trigonopa, but has no radial tubes.
Dimensions.—Diameter of the sphere 1.0 to 2.0; tubes 0.1 to 0.15 long, 0.007 to 0.01 broad.
Habitat.—Central Pacific, Stations 270 to 274, surface.