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as belonging to that species. The description of the "Challenger" specimen was given from a 

 single specimen. 



The valves of this specimen are to a large e.xtent covered by chitinous membrane, 

 leaving (exactly as in the specimen of Sc. moluccamwi^ described in the "Challenger" report) 

 the aijices of the valves uncovered. This membrane was moreover wanting on the left side of 

 the capitulum, at the places from which I had removed the other Scalpellums. Continuing to 

 take away this chitinous membrane I discovered that the area of each valve was distinctly 

 limited by a clear line and that the calcareous valve only occupied a part of that area : only 

 after this chitinous covering was removed was it possible to make out the exact shape of each 

 valve. To decide whether Sc. regium and Sc. molucca7mm are really different species, and also 

 to which the present specimen belongs, it would by all means be necessary to deal wath the type 

 specimens as I have now done with the "Siboga" Scalpellum. Fig. 13 of PI. W\ represents that 

 specimen, seen from the left side after the chitinous covering was removed from the capitulum. 



Whereas the "Challenger" took the species at Lat. 4°2i'S. and at Long. i29°7'E. 

 from a depth of 1425 fathoms (about 2565 m.), H. M. S. "Siboga" collected it at: 



Stat. 271. December 21, 1899. Lat. 5°46'S., Long. i34°o'E. Depth 1788 m. Bottom: bluish 

 green mud of a uniform appearance. 



15. Scalpelhim hamulus n. sp. PI. YH, fig. 14 and \\a. 



Surface of the capitulum and of the peduncle covered by a thin membrane with very 

 short hairs. Valves fourteen. Carina simply and strongly bowed with a nearly flat roof which 

 is very wide at the base. Upper latus very narrow at the base. Rostrum triangular. Valves of 

 the lower whorl small with exception of the rather well developed carinal latus. Umbo of the 

 latter at the upper extremity. 



This beautiful species is represented by one specimen only. 



The capitulum is rather robust, thick especially in the under part ; it is of an elongate 

 oval .shape with the apex slightly produced. The valves of the lower whorl are relatively small, 

 the carinal latus excepted. The valves touch each other and are covered by a membrane which 

 is clothed with short hairs. 



The scutum is very broad at the base, the lateral margin not beginning above the 

 apex of the infra-median latus (as is the rule in this genus) but above the middle of the upper 

 maro-in of the carinal latus. Apex produced; tergal margin slightly hollowed out; occludent 

 margin convex. Not quite twice as long as broad. 



The tergum is likewise rather broad. It has the scutal margin convex and the occludent 

 mar^nn also convex. The apex is slightly produced and terminates in a short but rather sharp 

 and feebly recurved point. 



The carina is simply bowed with a nearly flat roof widening verj- considerably from 

 the apex to the base. The roof is slightly convex laterally and its borders insensibly pass over 

 into the rather narrow side parts. 



The upper latus is of a triangular shape with the umbo at the apex fitting into the 

 ano-le formed by the lateral margin of the scutum and the scutal margin of the tergum. The 



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