Page:Scientific results HMS Challenger vol 18 part 2.djvu/106

982 6. Podocoronis hexapodiscus, n. sp.

Basal ring violin-shaped, with six conical, vertically descending feet, half as long as the sagittal ring; two of them are sagittal (arising from the two basal corners of the sagittal ring, caudal and sternal feet); the other four are lateral, and prolongations of the forked basal parts of the frontal ring, which is inserted on the basal ring with two forked branches; the anterior correspond to the pectoral, the posterior to the tergal feet of Hexaspyris. All the rings are thorny.

Dimensions.—Height of the frontal ring 0.11, breadth 0.17.

Habitat.—South Pacific, Station 295, depth 1500 fathoms.

Definition.—Basal ring with numerous (eight to twelve or more) descending feet.

7. Podocoronis petalospyris, n. sp.

Basal ring violin-shaped, with ten to twelve flat lamellar, vertically descending feet, about as long as the ovate sagittal ring. Frontal ring twice as broad as long, elliptical. All rings nearly smooth. Similar to a Petalospyris without lattice-work.

Dimensions.—Height of the frontal ring 0.1, breadth 0.2.

Habitat.—Fossil in Barbados.

8. Podocoronis polypodiscus, n. sp.

Basal ring elliptical, with fifteen to eighteen conical, curved, descending feet, half as long as the ovate sagittal ring. Frontal ring kidney-shaped, one and a half times as broad as long. All the rings armed with short conical spines.

Dimensions.—Height of the frontal ring 0.12, breadth 0.18.

Habitat.—Central Pacific, Station 273, depth 2350 fathoms.

Definition.— with eight large gates (four superior lateral and four inferior basal). Skeleton composed of three complete rings, perpendicular to one another; two of which are vertical (the primary or sagittal and the secondary or frontal ring), the third is horizontal (the tertiary or basal ring).

Definition.— with eight large, simple gates of different sizes; the four upper or lateral gates larger than the four lower or basal gates. Skeleton composed of three simple complete rings, perpendicular to one another.