.i-, beloi rhe description of the "Challenger" specimen was given from a 



iniiii 



■ I this specimen are to a largi red by chitinous membrane, 



in the specimen of Sc. moluccanum, described in the "Challenger" report) 



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



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



takt- awa\ this chitinous membrane I discovered that the area of each valve was distinctly 



limited by lim • and tliai 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 ol each 



lecide whether Sc. regium and Sc. moluccanum are really different species, and also 



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



is 1 have now done with the "Siboga" Scalpellwn. Fig. i .; of PI. \'1I represente that 



men, seen from the left side alter the chitinous covering was removed from the capitulum. 



Whereas the "Challenger" took the species at Lat. 4 2 1 ' S. and at Long. 129 7 ' 1-.. 



■tli of 1425 fathoms (about -505 m.), Il.M.S. "Siboga" collected it at: 



St.it. 271. December 21, [899. Lat. 5 46 S., Long. i34°o'E. Depth [788 m. Bottom: bluish 

 green mud of a uniform appearance. 



15. Scalpellwn hamulus n. sp. PI. VII, fig. 14 and \j\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. l'mbo 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. I he valves touch each other and are covered by a membrane which 

 is clothed with short hairs. 



The scutum is very broad al the base, the lateral margin not béginning above the 

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

 margin 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 

 margin also convex. The apex is slightly produced and terminates in a short luit rather sharp 

 and feebly recurved point. 



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

 the a ■ the base. The root" 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 

 irmed by the lateral margin of the scutum and the scutal margin of the tergum. The 



86 



