MOLLUSCA. 



III.-AMPHINEUEA 



By Edgar A. Smith, I.S.O. 



CHyETOPLEURA MIRANDA.* 

 (PL II., figs. 13-13g.) 



Animal elongate, more than twice as long as broad ; valves thin, acutely keeled 

 along the middle, fiatly sloping on each side, standing erect posteriorly, one above the 

 other ; anterior valve (fig. 1.3b) with eight to ten slender radiating costse, slender above, 

 and gradually thickening towards their extremity, radiately striate or sulcate between 

 the ribs; medium valves (fig. 13c) with a single costa on each side, the rest of their 

 surface being radiately sulcate or striated and marked with fine lines of growth ; the 

 posterior valve (fig. 13d) has the mucro behind the centre, and, besides the radiating 

 sulcation, exhiljits one or two more conspicuous sulci diverging laterally from the apex ; 

 the girdle is clay-coloured, rather broad, fleshy, closely beset with short spicules ; colour 

 of valves dirty whitish, excepting the third and seventh, which are more or less 

 reddish ; insertion plates thin, that of front valve with nine fine, short slits corres- 

 ponding to the external ribs (fig. 13e) ; intermediate valves (fig. 13f) with a single 

 lateral slit, posterior valve (fig. 13g) with six slits. 



Length (including girdle), 55 millim. ; diam., 25 ; height from sole of foot to the 

 apex of the fourth valve, 1 2 millim. 



Winter Quarters, Holes 6, 10. In 125-130 fathoms. 



Three specimens of this interesting chiton were obtained, all agreeing in coloura- 

 tion, which is remarkable, as only the third and seventh valves are stained with red, 

 the rest being dirty whitish. The gills extend about two-thirds along the side of the 

 foot. 



* Mr. Smith has this morning received Dr. .1. Thiele's report on the Chitons of the " deutscher Tiefsee 

 Expedition," in which (vol. ix., p. 332) this species is noted as Notochiion [g.n.] mirandus ; the* locality cited 

 (Bouvet Island) shows the wide distribution of the species. — Ed., Oct. 22, 1906. 



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