82 On Some Neiv Marine Mollusca. 



difference between the present species and the Tasmanian 

 shell is that the latter is simply striate, while this is corded. 



Chiton inoknatus, 0. t, figs. 8, 9. C. t. ovalis, tenui. 

 depressa, baclia saturata, concolor, ubique minutissime 

 punctata ; valvis cequalibus, carinatis, vix rostratis ; areis 

 later alibus p arum elevatis,striis radiantibus obsoletis; areis 

 centr alibus, lineis tenuibus concentricis striatis; valvis ter- 

 minalibus haud magnis, obscure costatis, costulatis, 

 rotundatis,marginemembranacea pilosa. Punctis in valvis 

 confertissimis, depressis. Long. 40, Lat. 25, Alt. 5 mil. N. 

 Tasmania. 



Shell oval, thin, depressed, of a uniform deep brown, very 

 finely dotted all over with minute depressions like the top 

 of a thimble, valves of a uniform width, keeled, slightly 

 beaked; lateral areas very little elevated with obsolete 

 radiate striations; central areas finely marked with concen- 

 tric striae : terminal valves not large, obscurely ribbed with 

 broad rounded ribs; margin membranaceous, covered with 

 scattered short silvery hairs. 



The distinction of this species is its very uniform orna- 

 mentation. In most of the Chitons there is some marked 

 difference between the lateral and central areas of the 

 valves, but here all seems uniform in the colour as well as in 

 the ornament. The lateral areas have concentric lines like 

 those of growth. The minute dots with which the surface 

 is pitted is a feature which this species shares with many 

 others in Australia, but the marks are finer and more shallow 

 than usual. The species is very rare. 



Austktella, nov. gen. Testa oequivalvis, inoequilateralis 

 postice parum prodncta, periostraca induta, concentrice 

 lamellosa, ligamentum externum, dente cardinalis uno, 

 arcuato, inconspicuo ; intus haud iridescenti, impressione 

 pallii sinu nullo, duobns impressionibus muscularibus, 

 lateralibus. In locis paludosis sub-salinis vel dulcis prope 

 Bowen, Portis Denisoni ubi olim ab indigenis barbaris ut 

 alimentum abundanter conquisita et nunc extant innumeris 

 testarum fragmentis in cumulis arenacis prope mare. A 

 Spatha genus Unionidce testa non iridescentesed lamellosa sat 

 dAstincta. Nomen duxi ab Australia cui adhuc numquam 

 a naturalistis genus concliiliorum sit dedicatum. 



It is with considerable hesitation that I erect this new 

 genus in a science which has already been so heavily bur- 

 dened with useless and confusing genera ; but I cannot find 

 any of the existing divisions which will in any way meet the 



