146 ISCHNOCHITON-ISCHNORADSIA. 



Lateral areas somewhat raised, sculptured with low, uneven, some- 

 what nodulous radiating riblets, and some concentric growth-wrinkles. 

 Central areas smooth except for a very dense and regular microscopic 

 granulation. End valves having radiating riblets ; mucro rather 

 prominently raised ; posterior slope concave. Interior blue-green, 

 with pink and olive rays. Sutural plates rounded ; sinus smooth, 

 not toothed. Anterior valve having about 19, central valves 3-4, 

 posterior valve 18 slits. Teeth thick but sharp ; eaves wide, solid. 



Girdle covered with smooth, solid, pebble-like scales, which toward 

 the outer edge, are subcarinated. Length 43, breadth 23 mill. 



Adelaide, S. Australia. 



Chiton novcehollandice (GRAY, MSS. in Brit. Mus.) KEEVE, Conch. 

 Icon., t. 21, f. 142, May, 1847. 



This species has much the appearance of I. australis, but it differs 

 totally in the sculpture of the central areas, and somewhat in that 

 of the lateral areas. The girdle is just like that of australis, except 

 that the pebbly scales are smaller in a specimen of the same size. 

 Carpenter erroneously considered this species a synonym of Chiton 

 (Radsia) goodalli. 



I. LIJGUBRIS Gould. Unfigured. 



Shell small, solid, punctate, elongate-ovate, slightly carinated, 

 emerald-green. Central areas sculptured with longitudinal lirse, 

 smooth at the apices. Lateral areas elevated, having . branching 

 nodulous lirse. End valves radiated at the margins, umbo sub- 

 central. Girdle wide, covered with large transverse convex scales. 

 (Old.-) _ 



Interior : end valves having 19-24, central valves 2-4 deep slits ; 

 teeth acute, sometimes a little rugose at the margins ; eaves very 

 short, spongy ; sinus broad, flat, smooth. Girdle imbricated with 

 very solid narrow, nearly smooth scales. ( Qpr.) 



Length 25, breadth 15 mill. (Old.} 



Habitat unknown. 



Chiton (Lophyrus~) lugubris GOULD, Proc. Bost. Soc. Nat. Hist, 

 vii, p. 163, Dec., 1859 ; Otia Conch., p. 116. Lepidoradsia lugubris 

 Gld, CPR., MS. 



The girdle, says Carpenter, is very like that of I. australis, from 

 which the strong sculpture distinguishes this species. 



