168 



anis, rufeseentibus eburneo lineatis ; extremitate postieii lcviter 

 truncata demum subsinuata ; declivitate umbonali obtuso: cardo satis 

 validus ; dentibus lateralibus duobus. Long. 10; alt. 9 ; lat. G millim. 

 Inhabits Loo Choo. W. S. 



Very like V. /)' ruin Gd, and ]m<silt!y the same. It is less pouched, 

 ami destitute of concentric lamellar striae and the two peculiar 

 white umbonal rays, though there are vermicular opaque markings. 



Tkli.ixa (Arcopagia) cratitia. T. tenuis, Iivida, eompressa, 

 ovato-triangularis, eostis acutis reelivantibus ad 30 (minoribus postiee 

 interpositis) radiata, et laminis crcbrisconcentricis reflexis costas equi- 

 tantibus eancellata ; umbonibus medianis; marginibus dorsalibus 

 declivibus, subrectis; extremitate postica acute rotundata, et plica 

 incoDspicua, umbonali instructs ; margine ventrali arcuata, pectinata; 

 eavositas nitida, sulculata. Long. 15; alt. 11; lat. 5 millim. In- 

 habits Loo Choo, sandy bottom, 8 fathoms. W. S. 



Analogous to T. scoMnata, but no speeies has been described with 

 similar sculpture, which is much like that of Venus marica. 



Lutraria lucida. T. tenuis, alba, oblongo-ovata, subfalcata, 

 concentrice undulata; umbonibus ad trientem anteriorem positis, 

 acutis, emincntibus; extremitate antica acute rotundata, margine 

 dorsali declivi ; marg. postica concava, eompressa, extremitate trun- 

 cata ; declivitate umbonali obtusa : cavositate porcellani ; cardine 

 debili. Long. 40; alt. 20; lat. 8 millim. Inhabits Kagosima. W. S. 



Remarkable for its thin, lucid, fragile structure. A specimen in 

 Mr. Cuming's Coll. is larger than those collected by the Expedition. 



Saxidomis ahatus. T. crassa, exalbida, ovato-quadrata, epider- 

 tnide tenui rut'a induta, liris profundis recliventibus concentricis arata; 

 umbonibus ad trientem anteriorem positis; extremitate postica sub- 

 quadrata, oblique truncata, angulis rotundatis, modice hiante; delivi- 

 tate umbonali obtuso : extrem. antica minus elevata, rotundata, absque 

 lunula : eavositas alba, margine simphci : cardo validus, dentibus in 

 utraque valva 4, in v. dextra posteriori, in v. sinistra anteriori multo 

 majori. Long. 4.5 ; alt. 3 ; lat. 2 inches. Inhabits San Francisco. 



Smaller than S. NtUtalli, the posterior dorsal portion more elevated, 

 the valve more regularly convex, the beaks less prominent, which 

 with the furrows and epidermis give it very distinct characters. 

 Venus maxima Phil, cannot be very different from it. 



Tapes VEKNTCOSA. T. solida, oblongo-ovata, ventricosa, nitida, 

 superne levis alibi concentrice sulcato-plicata, fulva flavido maculata 

 et radiis hepaticis interruptis 4 ornata ; umbonibus vix antemedianis ; 

 lunula lanceolate ; facie dorsali antica excavata ; extremitate antica 

 acute rotundata ; margine dorsali postica subrecta, extremitate late 

 rotundata, subtruncata ; marg. ventrali lcnte arcuata ; margine 

 interna simplici. Long. 3; alt. 2; lat. 1.5 poll. Inhabits Kagosima 

 Bay and off Hakodadi Cape, in coarse sand, 20 fathoms. W. S. 



