196 



are more prominent than others in the proportion of two large to 

 one small. — G. B. S. 



Pectunculus injEQualis. Pect. testd subcordiformi, ohliqud, 

 inccquitaterali, altitndine longitudinem superante, gibhosd, obtuse 

 rad'iatim striatd, striis perjasciculos costiformes congcstis, inter- 

 stitiis striatis : long. 1'5, lat. 1 "15, alt. IS poll. 

 Hab. ad Panamam et Real Llejos. 



A very beautiful species, of a white colour, varied with blueish 

 grey, and very irregularly splashed over with dark chestnut brown : 

 the ligament is short, and a very small part of it is anterior to the 

 umbones. 

 Found in sandy mud in ten fathoms. — G. B. S, 



Pectunculus assimilis. Pcct. testd subcordiformi, ohliqud, in- 

 aquilateral'i, altius quam longd, suhgibbosd, radiatim sulcatd et 

 striatd, sti-iis per fasciculos costiformes congestis, inter stitiis la- 

 tiusculis, Iccvibus : long. 1*3, lat. 1, alt. \' 5 poll. 

 Hab. in America Centrali et Meridionali. 



Dredged in sandy mud and gravel, in from eight to twelve fathoms, 

 at Puerto Portrero and in the Bay of Guayaquil. 



It is a beautiful species, varying much in colour : in general the 

 ground colour is white, and it is splashed over with greyish brown, 

 rust-colour, and chestnut brown. — G. B. S. 



Pectunculus tessellatus. Pect. testd orbiculari, subglobosd, 

 albd, castaneo tessellatd et variegatd ; costis rotundatis, subdi- 

 stantibus, radiantibus : long. 0-9, alt. 1, lat, O'l poll 

 Hab. ad littora Columbiae Occidentalis. 



From sandy mud and gravel, in from eight to ten fathoms, at 

 Monte Christe and in the Bay of Xipixapi. — G. B. S. 



Pjictunculus strigilatus. Pect. testd orbiculari, subventri- 

 cosd, albidd, rosea tinctd et rubiginoso strigatd et variegatd ; costis 

 rotundatis, dista?itibus, radiantibus, interstitiis Icevibus ; long. 1, 

 lat. 0-65, alt. 105 p)oll. 

 Hab. ad Sanctam Elenam. 



Dredged from a depth of six to eight fathoms in sandy mud.— 

 G. B. S. 



Pectunculus longior. Pect. testa ellipticd, albicante, radi- 

 atim sulcatd, latere postico breviore, ferrugineo, ventrali roseo- 

 Juscescente, antico longiore ; intiis albicante, purpurascente-brun- 

 neo infect a ; long. 1-4', lat. 07, alt. 1-2 poll. 

 Hab. ad littora Brasilise. 



Two specimens only were brought from Rio de Janeiro. 

 This species is remarkable for being proportionally longer than 

 others. — G. B. S. 



Genus Capsa. 

 Capsa altiou. Cajosa testd oblongo-subtrigond, pallescente, intiis 

 violaced, epidermlde olivaced indtdd ; marginibus dorsalibus in- 

 clinatis ; latere antico rotuiidato-acuminato, postico subtruncato, 



