Chiton.] AMPHINEURA. 35 



3. Chiton Sinclair!, Gray, 1843. Plate 2, fig. 14 ; Plate 4, fig. 7. 



Chiton Sinclairi, Gray, in Dieff. N.Z.. ii, 263: Man. Conch. (1), xiv, 174, 

 pi. 36. f. 1-3 : P. Mill. S., ii, 196 : Wissel, Zool. Jahrb., xx, 627, pi. 23, 

 f. 38-44 ; pi. 24. f . 45-48 (anatomy). 



Shell oval, rather elevated, the dorsal ridge rounded, side slopes 

 rather straight, brown-black, irregularly striped with white. Anterior 

 valve with 15-18 granose ribs, through splitting increased to 24-30 in 

 adult specimens ; a number of higher ridges near the anterior margin. 

 Intermediate valves with the central areas smooth in the middle except 

 for a few growth-wrinkles, but having fine short longitudinal riblets at 

 the sides in front of the diagonal line ; these, however, are sometimes 

 absent ; lateral areas raised, with 3-4 radiate granose ribs, often 

 indistinct. Posterior valve with the central area smooth, posterior 

 area with 10-14 strongly granose ribs, some of them occasionally 

 bifurcate ; rnucro obtuse, in front of the middle. Girdle with im- 

 bricating, broadly rounded, and shining scales, which are microscopic- 

 ally very finely ridged. Colour brown-black, each valve irregularly 

 and raggedly striped with whitish, the head valve rarely pale with 

 dark rays ; sometimes the white predominates ; girdle banded with 

 light blue and black, the inner rows of scales mostly light brown. 

 Interior brownish-blue ; anterior valve with 10-13 slits, intermediate 

 valves with 1 slit on each side, posterior valve with 13 (rarely with 14) 

 slits ; teeth obtuse, very strongly crenulated ; sinus broad, distinctly 

 denticulate ; sutural laminae low, very broadly convex, straight, or 

 with a shallow concavity in the middle, white with a brown spot at 

 the base ; valve-callus strong, brownish ; eaves broad, spongy. 



Length, 28 mm. ; breadth, 18 mm. Other specimens are 30 mm, 

 by 16 mm. ; 19 mm. by 12 mm. 



Type in the British Museum. 



Hob. Both Islands, but rather local, and not common ; under 

 stones between tide-marks : Chatham Islands. 



Remarks. The species has been recorded from Tasmania, but 

 incorrectly. The short longitudinal riblets in front of the lateral 

 areas are sometimes cut up into granules by strong growth-lines. 

 Specimens are very often much eroded. 



4. Chiton Torri, Suter, 1907. Plate 4, fig. 8. 



Chiton Torri, Suter, P. Mai. 8., vii, 295, f. 2 in text. 



Shell small, elongate, smooth, dark brown. Anterior valve with 

 11 indistinct riblets (obsolete in one specimen), crossed by fine growth- 

 lines, the whole surface minutely wrinkled. Of the intermediate valves, 

 the first is twice as long as the others, broadly rounded and smooth, 

 beaked, the central areas with minute transverse zigzag wrinkles, 

 jugum smooth ; lateral areas slightly raised, with concentric ridges, 

 very distinct near the margin, but gradually disappearing towards 



2* 



