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5- Solariclla (Ethaliopsis) callomphala n. sp. PI. IV, fig. i, \a\ PI. IX, fig. 9. 



Stat. 59. Western entrance of Samau-strait. 390 M. Coarse coralsand with small stones. 3 Spec. 



Stat. 95. 5°43'.5 N., U9°4o'E. 522 M. Stony bottom. 1 Spec. 



Stat. 98. 6°9'N., i20°2i'E. 350 M. Sand. 1 Spec. 



Stat. 100. 6°n'N., I20°37'.5E. 450 M. Dead coral. 3 Spec. 



Shell depressed-conical, polished, nacreous, with a thin, pellucid, white, external layer and 

 often a yellow line below the suture. Whorls 4 to 5, nucleus smooth, subsequent 2 whorls 

 microscopically spirally striate, crossed by weaker growth-striae, last 2 1 /;, whorls smooth, with 

 only very faint traces of growth-striae and spiral striae, but with a row of oval beads, just 

 below the conspicuous suture, periphery rounded; base nearly flat, impressed near the centre, 

 which is more or less filled by a thick callus, which is white, with radiating striae on its external 

 margin, granular near the columellar margin, and is ornamented there, with 4 or 5 granules. 

 The base of the shell round the callus, is likewise provided with radiating grooves. Aperture 

 subtriangularly rounded, very oblique, outer margin thin, slightly thickened interiorly, columellar 

 margin thickened, its upper end pressed to the body-whorl, with a thin layer connecting the margins. 



Operculum as described above, externally concave, yellow. 



Varying in altitude of the shell, in the presence or absence of the yellow subsutural line 

 and especially in the characters of the umbilicus, which is either closed, or more or less open. 

 This is not dependent on age ; for of the three specimens from Stat. 59, the largest and smallest 

 specimens have it open, the intermediate one quite closed. In those from Stat. 100, it is quite 

 closed or leaves perhaps a nearly imperceptible chink, in the specimen from Stat. 95, a con- 

 spicuous slit remains, that from Stat. 98 is closed. 



The shell, most resembling this species is Umbonium bairdii Dall ("Blake" Gastropoda 

 P- 359, PI- 21, fig. 6), but that species is less depressed, the beads are stronger, no inention is 

 made of spiral sculpture on the post-nuclear whorls, nor of radiating sculpture on and around 

 the callus, or of oranules on the columellar maroin. I think these characters would not be 

 overlooked by such an exact observer as Dall, and so I may conclude to its specific distinction. 



If I had not examined the radula, I certainly should have located this species in the genus 

 Ethalia, but the radula is quite of the same type, as that of the other species of Solariclla. 

 It is short, with a rather restricted number of uncini, and the shape of the teeth agrees with 

 that of the known species. The rhachidian tooth (R) has a subquadrate body, narrower in front, 

 with concave upper and convex basal margin, its cusp is large, longer than the base, with about 

 4 to 6 denticles on each side of the median denticle, the first lateral (1) has a subquadrate 

 body, its cusp has very small denticles at its proximal, more conspicuous ones at its distal 

 margin, the second lateral (2) has a similar body, with larger cusp and more numerous denticles 

 at its distal margin ; the body of the third lateral (3) is elongate, with a moderate cusp and 

 only a few denticles, the fourth (4) has a very large cusp, with about 10 small denticles and a 

 rhombic body, moreover I see a fifth lateral (5) without cusp, as described before in S. mutabilis. 

 Perhaps this tooth exists in many or in all the species, but it is so much covered by the other 

 teeth in their normal position, that it may be easily overlooked. The uncini are not very numerous, 

 and as far as I can see, they have simple cusps. Except the callus this species resembles 



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