38 AMPH1NEURA. [Polyplacoplwra. 



side, and posterior valve with 10 (rarely 9) slits ; teeth minutely pec- 

 tinated ; sinus deep and narrow, denticulate ; sutural laminae very 

 broadly convex ; valve-callus not very stout ; eaves solid. 



Length, 14mm. ; breadth, 11 mm. Divergence, 100-105. 



Type in Mus. Hist. Nat., Paris. 



Hob. --Tasman Bay, type (Q. & G.) ; Cook Strait; Dunediu ; 

 Foveaux Strait ; Stewart Island. In deep water, on oysters or dead 

 shells. 



Remark. The type of Adams's C. insculptus was collected in New 

 Zealand by Strange. 



7. Chiton clavatus, Suter, 1907. Plate 4, fig. 11. 



Chiton clavatus, Suter, P. Mai. S., vii. 296, f. 3 in text. 



Shell small, elongated oval, acutely raised, surface of all valves 

 minutely shagreened, with nodulous sculpture ; colour grey, some 

 valves brown. Anterior valve with 8 radiate ribs, each consisting of 

 3 flatly convex nodules, the uppermost small and round, the follow- 

 ing large and squarish, the lowest a little smaller, oblong ; posterior 

 margin crenulate. Intermediate valves have the first longer than the 

 others, sharply angulate, slightly beaked ; central areas with 5-6 deep 

 longitudinal furrows on each side, centre smooth ; lateral areas raised, 

 with an anterior and posterior broad rib bearing flatly raised squarish 

 nodules, which are more numerous on the posterior rib ; seventh 

 valve having a few central nodules on the lateral areas, marking a 

 third rib ; sutures strongly and bluntly crenulated. Posterior valve 

 with 2 concentric rows of round nodules, representing 10 radiate ribs ; 

 mucro slightly in front of the middle, small and pointed, posterior 

 slope straight. Girdle with rather large, imbricating, convex, and 

 smooth scales, smaller on the inner side. Colour of the first, second, 

 seventh, and eighth valves ash-grey, the other valves greyish-brown 

 with white spots along the ridge ; girdle uniformly grey. Interior : 

 Anterior valve with 8, intermediate valves with 1. and posterior valve 

 with 11 slits ; teeth pectinate. 



Length, 14 mm. ; breadth, 9 mm. Divergence. 95. 



Type in my collection. 



Hob. Rangitoto Island, near Auckland, between tide-marks ; a 

 single specimen (H. S.). 



Remarks. Of the New Zealand species, C. limans is the nearest, 

 from which, however, it is easily separated by the smooth not sharply 

 raised tubercles, and the rounded not pointed smooth scales 



8. Chiton Huttoni, Suter, 1906. Plate 2, fig. 17: Plate 4, fig. 12 



Chiton Huttoni. Suter, T.N.Z.I., xxxviii, 320, pi. 18, f. 1-0. 



Shell oblong-ovate, angularly raised, valves striated throughout, 

 jugum smooth, girdle with rounded scales ; colour yellowish-olive, 

 dull to dark green or brick-red ; interior whitish. Anterior valve 



