132 nuculidje. 



costis concentricis crassis subremotis, lirisque radiantibus intersti- 

 tialibus undique decussata. Margo ventralis arcuatus, utrinque 

 acclivis. Area profundi imprcssa, elliptico-lanceolata, subduplex, 

 superne longitudinaliter rugosa, infeme (etiamque lunula angusta) 

 transversiin costellata. — Very small, peaked-ovate, more or less 

 ventricose, white (without epidermis?), devoid of indented ray, 

 everywhere coarsely ribbed (dorsal areas excepted). Ribs longi- 

 tudinal (not concentric) ; their intervals, which are quite as broad 

 as the ribs, and in front, where the latter are somewhat divergent, 

 rather broader, everywhere adorned with radiating lyras. Sides 

 equal or very nearly so ; anterior end somewhat narrowed and 

 rounded. Posterior side acuminated, the tip bluntly acutangular, 

 subcentral, scarcely upturned. Dorsal slopes moderate; front 

 one convex ; hinder one at first straightish, then convex, eventually 

 incurved. Ventral margin arcuated, rising at both ends. Lunule 

 narrow, barred across ; escutcheon rather large, lanceolated-elliptic, 

 deeply and abruptly impressed, almost double, wrinkled length- 

 ways in the middle, costellated across at the circumference. 

 Hinge-margin very broad : cartilage-pit minute, perpendicular, 

 triangular. 



47. L. Brookei, Hanley, f. 106. — T. minuta, subaequilateralis, 

 late ovato-conica, postice repente acuminata vixque recurvata, 

 ventricosa, eburnea, radii impressi expers, undique concentrice 

 costata ; interstitia costarum angustarum a3qualiter lata, in medio 

 lsevia, utrinque creno-lirata. Margo dorsalis antiee brevis, satisque 

 declivis ; postice rectiusculus, declivis; ventralis conspicue ar- 

 cuatus, postice rectior multumque acclivis. Area magna, plica 

 umbonali depressa creno-costata defimta. Lunula sublsevigata, 

 sulco circumscripta. — Minute, rounded ovate-conic, tumid or ven- 

 tricose, glossy ivory-white, barely gaping even posteriorly, devoid 

 of indented ray or raised umbonal ridge, concentrically ribbed 

 throughout (dorsal areas excepted) ; ribs narrow, prominent, nu- 

 merous, only as broad as the intervals, which are smooth in the 

 middle and rather obscurely creno-lyrated at each extremity. 

 Sides very nearly equal ; anterior one the shorter, peculiarly broad, 

 rounded ; posterior one abruptly and sharply acuminated, its tip 

 very short, subcentral, scarcely, if at all, recurved. Front dorsal 

 slope short, plano-convex, rather decided : hinder dorsal decided, 

 straightish. Ventral margin peculiarly arcuated, straighter and 

 much rising behind. Lunule defined by a sulcus, either smooth, 

 or with only fine raised wrinkles : escutcheon large, defined by 

 the creno-costated projection of the posterior ridge. Teeth rather 

 numerous on either side. — Of this little Leda I have seen but 



