390 PLEUROTOMID.E. 



corded it as Norwegian (Bergen to Finmark) ; and it 

 has also been taken on the same coast by M' Andrew 

 and Barrett, Danielssen, Sars, and Lilljeborg, at depths 

 of from 30 to 150 f. 



My largest specimen of this graceful and remarkable 

 species exceeds an inch in length. 



As Loven well observed, it is allied to P. tor qua turn 

 of Philippi, a Calabrian fossil; but the dimensions 

 and figure given in the latter's work represent a much 

 less slender shell. The lines of growth vary in strength, 

 and are not so conspicuous in living as in dead speci- 

 mens. 



9. P. septangtjla'ris'*, Montagu. 



Murex septangularis, Mont. Test. Br. (i.) p. 260, t. 9. f. 5. Mangelia 

 (Beta) septangularis, F. & H. iii. p. 458, pi. cxii. f. 6, 7, and (animal) 

 pi. TT. f. 3. ' 



Body white, powdered with minute flake-white points : 

 mantle rather thick at the edges : pallial tube fleshy, extending 

 beyond the canal of the shell : head compressed, narrow, with 

 a vertical fissure below it, from which the retractile proboscis 

 issues : tentacles short, " setose ' : [?], coalescing at their bases: 

 eyes on the external points of thick stalks annexed to the ten- 

 tacles, at about two-thirds of their length : foot rather narrow, 

 truncated in front, and slightly auriclecl, moderately long, with 

 the termination nearly as broad behind as in front, without a 

 trace of a distinct point, although the tail is often more or less 

 notched. (Clark.) 



Shell forming an elongated cone with a produced base, re- 

 markably thick, opaque, somewhat glossy : sculpture, strong, 

 angular, and rather prominent longitudinal ribs, which extend 

 to the suture but not to the base ; they are flexuous on the 

 body-whorl, and nearly straight on the upper whorls, where 

 they usually form a continuous series along the spire ; their 

 interstices are concave ; the labial rib is very large, and aged 

 specimens frequently have a similar rib or varix on the middle 

 of the body-whorl ; there are from 7 to 9 ribs (usually 7 only) 

 on the body-whorl, and one less on the next whorl, the number 



* Heptagona], or having seven angles. 



