MOLLUSCA. 
Il1l.-AMPHINEURA. 
By Enear A. Smita, 1.8.0. 
CHATOPLEURA MIBANDA.™ 
(Pl. IL, figs. 18-132.) 
ANIMAL elongate, more than twice as long as broad; valves thin, acutely keeled 
along the middle, flatly sloping on each side, standing erect posteriorly, one above the 
other ; anterior valve (fig. 13b) with eight to ten slender radiating coste, slender above, 
and gradually thickening towards their extremity, radiately striate or sulcate between 
the ribs; medium valves (fig. 18c) 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, exhibits 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, 12 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. J. Thiele’s report on the Chitons of the “ deutscher Tiefsee 
Expedition,” in which (vol. ix., p. 832) this species is noted as Notochiton (g.n.] mirandus ; the locality cited 
(Bouvet Island) shows the wide distribution of the species.—Ep., Oct. 22, 1906. 
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