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The rostrum is very small, triangular, with the base of the triangle directed towards 

 the scuta. 



The rostral 1 a t u s is quadrangular with the longer scutal and shorter basal margins parallel. 



The infra-median latus is triangular; umbo at the upper extremity. 



The carina! latus has a pentagonal shape with the umbo at the upper extremity, 

 at the angle formed by the carinal and upper lateral margin. 



The peduncle is cylindrical and relatively short; the scales are placed in transverse 

 rows and are large and of an irregular shape; they seem to be broken off from the lower 

 part of the peduncle. 



Size. Length of the capitulum 3,4 mm., of the whole animal 4,7 mm. 



This species was taken at : 



Stat. 227. November 13, 1S99. Lat. 4°5o'.sS., Long. i27°59'E. Depth 2081 m. Bottom: grey 

 mud with an upper layer of brown, both mixed with sand. One specimen. 



Observation. This species is, most probably, nearly related to Sc. hirsutum Hoek 

 collected by the "Challenger" at a depth of 1500 m. between Celebes and Halmaheira. There 

 are, however, several more or less important differences between the two forms, which I think 

 make it preferable to consider them as distinct; e.g. in the shape of the scutum, tergum and 

 upper latus, but especiall)- in that of the carina and the rostrum. As Sc. hirsiitiiin has a capitulum 

 of 6 mm. and Sc. ciliatiuu of 3,4 mm. only, the latter ma)- be found to represent a not quite 

 full-grown stage of the first — a somewhat richer material, however, is necessary to make this out. 



19. Scalpelhwi pellicat2im n. sp. PI. \TI, fig. 18, \'&a and 19. 



Valves fourteen, covered by membrane of a velveteen appearance. Carina simply bowed, 

 roof nearly flat not bordered by ridges; apex projecting freely. Upper latus quadrangular. 

 Rostrum triangular. Infra-median latus triangular. Carinal latus with the umbo projecting beyond 

 the line of the carina. 



This species is represented by one large, one fairly large and half a dozen small specimens. 

 The largest specimen is figured. 



The capitulum is white, covered by a membrane which bears short hairs standing 

 off from the surface and thus giving it a velveteen appearance. Most of the valves are separated 

 from one another by chitinous interspaces. The capitulum is broadest at its base, its length is 

 less than one and a half times the breadth. 



The scutum is quadrangular; the occludent margin is slightly convex, the basal and 

 lateral margins are nearly straight, the tergal margin slightly hollowed out and forming with 

 the occludent margin a slightly recurved apex. 



The tergum has the carinal margin divided into two parts: a larger lower part which 

 is convex and a shorter upper part which is straight. This upper part of the carinal margin 

 runs parallel to the scutal margin : hence the whole valve has the shape of a parallelogram. 



The carina is simply and strongly bowed and has the umbo at the apex which projects 

 freely beyond the carinal margin of the tergum. The roof of the carina is broad at the base, 



91 



