Calliostoma imperiale: Lischkeia imperialis: Lischkeia deichmannae: Description.—Shell elevated, trochoid in shape, conspicuously sculptured, rather large but thin and light in construction; height 54 mm, maximal diameter 42 mm. Nuclear whorls missing, about 8,5 postnuclear whorls remaining. Spire extended, produced at an angle of 58°; suture impressed in a distinct channel; whorls convex, shouldered. Two spiral cords set with prominent conical nodules delimit a broad, flat periphery. A pair of weak spirals, thickened at intervals where they are crossed by axial lamellae, bounds a narrow, flat shelf adjacent to the suture, which is developed a short distance below the lower peripheral cord. This results in a distinct channel containing the suture, which develops along a spiral that becomes nodose on the last half of the body whorl and forms a distinct boundary for the base. Base moderately convex, ornamented with ten spiral cords that become nodose toward the edge of the outer lip. Axial sculpture consists of conspicuous, thin, undulating and anastomosing, raised lamellae which, in turn, are marked with microscopic growth lines. Aperture subcircular, with a thickened, reflected outer lip evidently indicative of maxi¬mal growth, produced at an angle of about 45° from the base. Columella arched, smooth, without teeth. Parietal wall with a thin glaze that is nacreous on the pillar and in an area adjacent to the sutural angle, but porcellaneous in the intervening area. Inside of outer lip nacreous. Outer surface creamy white, semiopaque, possibly allowing a nacreous lustre to show through in living material.

Calliostoma imperiale: Lischkeia imperialis: "Shell with five (?) whorls, globosely conical, white, extremely thin; umbilicus reduced to a mere chink under the thin callus of the upper part of the pillar lip. Mouth rounded rectangular, pillar somewhat concave, margins all thin; base flattened convex, with seven revolving ribs, the outermost of which is just within the periphery, crossed by radiating lines of growth, regular and very fine, but raised into low, very sharp lamellae, which pass over the periphery on to the upper surface of the whorl; the last is provided with two strong revolving ribs, one of which forms the periphery, while the other lies a little less than half-way from the first toward the suture; two indistinct threads run in the vicinity of the suture; on the revolving ribs above mentioned there are regularly disposed sharp rough tubercles (seventeen on the last whorl), most prominent on the middle carina; the above mentioned lamellae are arranged with a regular irregularity (which gives a shagreened appearence to the surface) between the carinae, and are still coarser and more elevated over the threads near the suture, forming there a double row of scales partly obscuring the suture, which is nevertheless rather deep. Alt. of last whorl, 10.0, Lat. 13.0, Alt of apperture 5.5, Lat. of same 6.25 mm. Off Cuba, Pourtales in 200 fins."

Calliostoma imperiale: Lischkeia imperialis: Lischkeia deichmannae: On first sight, Lischkeia deichmannae is strikingly similar to the type-species, L. monilifera (Lamarck) (= L. alwinae Lischke) from Japan. Comparison of specimens reveals significant differences, however. In L. deichmannae the spire is more extended, the base more inflated and convex, and the umbilical callus completely seals over the umbilical depression. In L. monilifera, the edge of the callus is free so that the shallow spiral channel bordering the columella is roofed over by its advancing edge but remains open terminally. Also, in L. monilifera the spiral cords are more distinct, beaded at their intersections with narrow axial cords. In L. deichmannae, the spiral sculpture is obscure except for the two prominently nodulose cords above and below the periphery and those on the base, and the lamellate axial sculpture is very conspicuous. Specimens of L. monilifera from Sagami Bay, Honshu, Japan, in the collections of the National Museum of Natural History (343262) have a height of 37.6 mm, diameter 33.8 mm, angle of spire 73°. From Tosa Bay, Shikoku, 70 fms = 128 m (605948), height 45.5 mm, diameter 44 mm; height 36.7 mm, diameter 32.8 mm; and height 37.8 mm, diameter 34.5 mm. From Tanabe, Kii, Honshu (273648), height 35.2 mm, diameter 31.5 mm; and height 35.8 mm, diameter 32 mm.
Lischkeia deichmannae more closely resembles a specimen of Lischkeia from off Ternate (ALBATROSS Sta. 5617, 131 fms = 240 m; USNM No. 239250), which has a similarly elevated spire, more convex base, and raised axial lamellae. In this example, however, the spiral sculpture is distinctly developed, the base is not so sharply set off from the side of the body whorl, and the major spiral cords on the peripheral half of the base are strongly nodose.

Calliostoma imperiale: Lischkeia imperialis: The present species differs from Ginebis crumpi in having two tuberculous rows and subsutural small beaded rows but the latter has three conspicuous tuberculous rows without subsutural beaded rows.

Calliostoma imperiale: Lischkeia imperialis: Lischkeia deichmannae: Type-Locality Off St. Lucia, Lesser Antilles.
Record.—GERDA Sta. G-897, off Arrowsmith Bank, Yucatan, 20°59'N, 86°24'W, 293-210 m, 10 September 1967. A fragmentary specimen consisting of the thickened palatal lip and part of the base.

Type locality: Off Cuba, 200 fathoms, Recent.
Recent distribution: Off Cuba 200 fathoms (Dall, 1881); off Pointe de Feu, St. Vincent 30-50 fathoms (Rehder, 1955); off Habana, Cuba 182 fathoms (Rehder, 1955).