the latter genus is a simple lattice-plate, it here becomes more or less spongy, and sometimes forms a very dense and delicate wickerwork. The apical horn and the three basal feet are commonly also fenestrated. The two annular strictures, which separate the cephalis from the conical cupola and the inflated thorax, are commonly not so distinct as in the preceding genus. Some species belong to the largest Spyroidea and reach more than half a millimetre in length.
1. Lamprospyris darwinii, n. sp. (Pl. 89, fig. 13).
Shell nearly pear-shaped, with two distinct annular strictures, and uneven papillate surface. The total length is equal to twice the greatest breadth, and to seven times the length of the ring. Apical horn free, irregularly branched and fenestrated, as long as the included columella beyond it. The three diverging feet are strongly curved, S-shaped, and completely included by loose lattice-work. In the middle of their length they give off a simple strong lateral branch. The loose arachnoidal lattice-work is rather equally developed.
Dimensions.—Length of the entire shell (including the apophyses) 0.5, greatest breadth 0.25, ring 0.07 long.
Habitat.—Central Pacific, Station 271, depth 2425 fathoms.
2. Lamprospyris lyellii, n. sp.
Shell slender, pear-shaped, very similar to the preceding species, but differing in the following characters—the branched horn is much larger and twice as long as the columella; the two annular transverse strictures (separating the three joints) are deeper. The free internal branches of the three included feet are forked. Lattice-work looser than in the preceding species.
Dimensions.—Length of the entire shell 0.6, breadth 0.2, ring 0.09 long.
Habitat.—Central Pacific, Station 266, depth 2750 fathoms.
3. Lamprospyris huxleyi, n. sp. (Pl. 89, fig. 14).
Shell ovate, spiny, with two slight annular transverse strictures; their length equal to one and a half times the breadth, and up to seven times the length of the ring. Apical horn quite included by the loose lattice-work of the large conical cupola, which is as long as the cephalis and thorax together. The three slender feet are also included in the lattice-work and only one-third as long as the shell, nearly vertical. Lattice-work much denser than in the two preceding species.
Dimensions.—Length of the shell 0.4, breadth 0.26, ring 0.06 long.
Habitat.—Central Pacific, Station 274, depth 2750 fathoms.
4. Lamprospyris hookeri, n. sp.
Shell ovato-conical, very similar to the preceding species, but smooth, not spiny. The apical horn and the three feet are much longer, not included in the network, but freely prominent, half
