Zuoluyicul Society. 355 



ZOOLOGICAL SOCIETY. 



August 13, 1844. — Professor Owen, V.P., in the Cliair. 



" Descriptions of new species of Area, chiefly collected by H. Cu- 

 ming, Esq. in the Philijipine Isliinds," by Lovell Reeve, Esq. 



Arc.v ORTi'SA. Area testd ohlongd, Modiohc/unni, luleribus obtitso- 

 I'otundatis, maryine ventra/i bj/sso paulidtnn hia/ife ; albd, epidcr- 

 viide niyricante siibsquamosd partiiii iiidutd ; radiutbn striutd, siriis 

 clevatis ; tnnbonibus depressiuseidis, approximatis ; ligamenli urea 

 parvd, angustd, profuiidt dcclivi. 



Conch. Icon. Area, pi. 12. f. 77. 



Hub. Const of Jaj)an (found under stones) ; Dr. Siebald. 



Very like a Modiula in shape, but not the recent analogue of the 

 fossil A. Modiolccformis of Dcshayes. 



Arca cuxealis. Area testd elongato-oblongd, luteribns stiperne 

 ungulutis, anlico brcvi, rotundato,postico elongato, ungnlato, eur'md 

 ub iimbune ad margincm deciirrente, margine ventrali bysso hiunte ; 

 pull nil' fused, epidennide molli lumeltutd indutd ; rudiatim striatd, 

 siriis elevatiSyfortiter granulosis, ared poslicd subindistinete nigri- 

 eostutd ; umbonihus subapproximutis, ligumenti ared latiuseuld, 

 coneavd, suleis ligamentariis anticis postieisque, subdistantibus. 

 Conch. Icon. Arca, pi. 13. f. 87. 



Hub. Zanzibar (found under stones at low water) ; Thorn. 

 The sculpture of this species corresponds precisely to that of the 

 Arca niutubilis ; the form of the shell is more depressly elongated, the 

 anterior side is shorter, and there are ligamentary grooves on the 

 posterior part of the cardmal area as well as on the anterior. 



Arca tenella. Area testd subcyUndraeeo-oblongd, Modioheforini, 

 tenui, subpellueidd, lateribus obtuso-rotundatis , margine ventrali 

 vix hiante ; palUde fusceseente, epidennide molli leviter indutd ; 

 radiatim subtilissime striatd, siriis granulosis ; umbonibus obtusis, 

 antiel' incurvis ; ligamenli ared antice latiuseuld , i^oslice lanceolato- 

 acuminatd. 



Conch. Icon. Arca, pi. 14. f. 91. 



I/ab. Islaud of Burias, Philippines (found under stones at low 

 water) ; Cuming. 



A delicate light brown shell, beautifully striated, with a soft scat- 

 tered epidermis. 



Arca setigera. Arca testd subquadrato-oblongd, lateribus rotun- 

 datis, poslieo lutiore, margine ventrali bysso vix hiante; rubido- 

 fuscd, epidermide fused seligerd indutd ; radiatim subtilissime 

 striatd, siriis elevatis, granulosis ; umbonibus subapproximutis, 

 anticr adjectis ; ligamenli ared angustd, declivi. 

 Conch. Icon. Area, pi. 14. f. 94. 



Hub. Zanzibar (found under stones at low water) ; Thorn. 

 This species approaches very closely to Arca laeerata ; it appears, 

 however, to be of an uniform smaller size, the posterior side is less 

 expanded, and the bristles are set in single rows. 



