212 Sou f hern Cross. 



LISSARCA AUCKLANDICA. 



(PI. XXIV., li-s. 14, 15.) 



Tost.n miniina, acquivalvis, valde inaeqiiilatcralis, convexa, purp\ireo-nifa, lincis 

 incrcnionti tenuibiis, iiostice sul>lamellatis, ticuli)ta, striis teiiuissiiiiis i)aucis 

 lK»stinc<liani8 radiantibus oniata; unibones Icviter ])roniincnteR, a]>i>r()xiiiiati 

 sc<l liauil conti<iui; dentos utiinque ciiciter (luinque; valvaniiii niaifjines 

 (]ira('tcr imtpo iiaitom anteiioreni niaiffinis ventralis ot ad mcdiviin lateris 

 ]K)stici) intus fortitcr denticulati. 



Longit. 4.i mm., diam. 2f, mm., alt. 3 J mm. 



Hahitat. — Auckland Islands, 10 fathoms. 



Closely allied to L. rnhro-fusca (Smith),^ from Kerguelen Island, 

 Init of a different form, being less oblong, having the nmbones less 

 terminal and the hinge-teeth somewhat different. A faint depression 

 is observable extending from the umbo down the posterior end. 



PECTEN COLBECKI. 

 (PI. XXY., fig. 11.) 



Te.sta tenuis, magna, coni])icssa, rotundata, pur]nireo-;ufa, oostis radiantibus circitcr 

 18 .subobsoletis, vel mininie ])n)niinentibus iiistnicta, concentrice O'nfertim 

 striata; margines dorsales aequales, late concavi ; linea cardinis aeque Icviter 

 concava; auriculae subaequales, autica valva^ dextrae iuferne baud profunde 

 sinuata ; pagina interna rufescens. 



Longit. 70 mm., alt. 70, diam. 10. 



Hahitat. — Franklin Island, 10 fathoms. 



A large very thin species of which oidy a single right valve 

 was obtained. It is remarkable for its rich purplish red or 

 Ttlum colour and the feebleness of the radiatiniir costation. The 

 costae are .somewhat more pronounced towards the umbo than upon 

 the rest of the surface, and are about twelve in number. Other 

 intervening and more feeble ribs are developed at a later period of 

 growth. The concentric sculpture consists of very fine thread-like 

 lamellae which are more remote in the early stages of growth than at 

 a later period. The auricles are striated ^^ith fine lines of growth, 

 and anterior, in the valve described, exhibits a faint raised ray down 

 the middle. 



There does not seem to be any species bearing sufficient 

 resend dance as to suggest a comparison with the present form. The 

 Arctic r. fjrccnlanflicns of Sowerliy has even a tliinner shell, but in 

 sizo, colour, and sculpture is quite distinct. 



' rbil. Trans. Roy. Soc, 1870, Vol. CLXVIII., p. 185, PI. IX., fig. 17. 



