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some others, in the new genus Solariellopsis. In the radula now under consideration, only 3 

 rows obviously belong to the median part, and it is strange that the cusps instead of being 



reflected, as is usually the case, 

 are stretched forwards. The rhachi- 

 dian tooth (R) has a subquadrate 

 body with somewhat protracted, 

 rounded posterior angles, the cusp 

 is lanceolate, with a rather sharp 

 point and numerous, very fine 

 denticles at the sides towards the 

 base, the lateral (i) is triangular, 

 with small denticles at the outer 

 margin of the cusp. The uncini 

 (U) which are not numerous, and of which perhaps the innermost must be considered as still 

 belonging to the median part, are long, slender, with small denticles near their top, if seen quite 

 flat, but which I cannot detect, if seen in the common, though reflected position. 



As the next species agrees in many respects with this description (the cusps are however 

 reflected) I have provisionally located it in this genus. The preceding genus, though allied by 

 its radula, differs very much conchologically. 



Fig, I. Teeth of Radula of Basilissa lai7ipr(i Wats. 



I. Basilissa sibogae n. sp. PL V, fig. 3; Fig. 2. 



Stat. 88. o°34'.6N., ii9°8.sE. 1301 M. Grey and yellow mud. 3 Spec. 

 Stat. 211. 5°4o'.7S., 120° 45^5 E. 1158 M. Coarse grey mud. i Spec. 



Shell conical, with concave sides, a sharp keel and slightly convex base, umbilicate, 

 nacreous under a thin, yellowish-white layer. Whorls 7, slightly convex, especially the lower ones. 



Nucleus smooth, shining ; 

 by the strong keel, which 

 is also visible on the upper 

 whorls, the suture is well- 

 marked. The sculpture con- 

 sists on the upper whorls 

 of thin, strongly curved, 

 radiating riblets, which are 

 rather crowded, but much 

 more distant on the lower 

 whorls, and nearly disap- 

 pear on the last two, these 

 riblets are slightly thickened 

 towards the upper suture 

 and below towards the keel, 

 which is crenulate by their crossing it; one or two spiral elevated striae may be observed on 



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Fig. 2. Teeth of Radula of Basilissa sibogae Schepm. 



