M0LLU8CA. 79 



arcuate. Last valve of a narrow acutely elliptic form, with the 

 mucin prohahly near the centre. Inferior of the plates greenish 

 blue, stained dark brown in the middle. Lamina of insertion in tho 

 front plate with about ten notches at unequal distances, leaving 

 different-sized teeth between them, which are striated on both sides, 

 but more strongly externally, tluur edges being sharp, but not 

 smooth. The central plates have a single minute notch on each 

 side, tho insertion-lamina being comparatively smooth on the upper 

 Burface and marked with a small brown spot on each side against 

 the edge of the valve. Tail-plate much thickened within along the 

 posterior edge, which is roughened by tine cross stria?, there being 

 no prominent teeth, and of course no notches. Mantle-margin 

 covered with small subimbricating oval granules. Length without 

 margin 16 millim. ; width of fourth plate 9. 



]Inl>. Port Curtis (Coppinger). 



The granules of the surface have an irregular concentric dis- 

 position, following to some extent the lines of growth. 



109. Chiton (Ischnochiton ?) adelaidensis. 

 Reeve, Conch. Icon. fig. 123. 



Hal. Port Molle, Queensland (Coppinger) : Port Adelaide (Reeve). 



The entire surface of this species is minutely granoscly reticulated, 

 the front valve, the lateral areas of the narrow central valves, and 

 the hinder area of the posterior are in addition somewhat irregularly 

 radiately sulcate. The prevailing colour is pale greenish, streaked 

 and dotted with red, the posterior margin of the valves being paler 

 than the general tone of the shell, and conspicuously spotted with 

 the same red colour. The grains of the mantle are smooth, arranged 

 in alternate greenish and reddish patches, and individually have a 

 dark spot generally on the outer side, which is only seen under 

 a lens ; those near the valves are considerably smaller than those 

 situated towards the edge of the girdle. Having parted the valves 

 of one of the specimens I find the front one has the margin of 

 insertion divided into seventeen unequal, squarely cut, slightly 

 crinkled, sharp-edged teeth, of which the two outer on each side are 

 the largest. The sixteen slits between the teeth are very small and 

 shallow. The second, third, fourth, fifth, and sixth valves have 

 on each side a single very small narrow central notch, from which a 

 groove or depression runs to the apex of each valve ; the seventh is 

 probably abnormal, having a single notch on the right side and two 

 on the left, and the terminal valve has nineteen similar slits. 



110. Chiton (Callistochiton) antiquus. 



Chiton antiquus, Reeve, Conch. Icon. fig. 109. 

 Callistochiton sarcophagus, Carpenter, MS. in Coll. Cuming. 



Hah. Australia (Reeve); Port Molle, Queensland (Coppinger); 

 Port Jackson, rare (Angas). 



Reeve's figure of this species is much enlarged, the type shell 



