C R B I S. 



Genus CORBIS, Cuvier. 



Testa transverse ovata, cequivalvis, crassa ; cancellatim 

 snilpta. Cardo ■utrinqiie valva dentihus diiobi/s 

 ' medinnis, et duohus lateraJihus, antiro s>tbapprnxi- 

 niato, postico distanlt. CartUago lifjamentifera 

 svbextema. ImpressionesmuscularesdvcB; impressio 

 pallii simplex. 



Shell trausveTselj ovate, eqiuvalve, tliick, -with a can- 

 oi'llated sculpture. Hinge in each valve with two 

 central teeth and two lateral, the anterior near, 

 the posterior remote. Muscular impressions two ; 

 impressions of the mantle simple. 



This genus, of which we know only two species, is 

 allied by the character of the hinge to the " Td/inidee," 

 but Viy general form and structure to the ^^ Veneridce." 

 Both species are products of 



Species 1. (Mus. Brit.) 



Connis FIMBRIATA. Cor. testa alba, iioiimnirjvam ad 

 latera ]iaUide sxihrosea, crassa, riigosd; costis inceqiia- 

 lihi/s iiiihrii-atig ct striis interstitialibus radiantibns, 

 el mill's traiisversis mbeoncentricis, vndidatis, can- 

 eellata : ii/tus alba, cardine sape aurantio mbroque 

 pallid'- tiiieta ; margine denliculato ; umbonibus 

 snbrentralibvs. 



The kimbiu.\ted Cordis. Shell white, sometimes pale 

 rose at the sides, thick, rugose ; cancellated with 

 unequal imbricated ribs and interstitial radiating 

 striffi, and transverse subconcentric, undulated 

 wTinkles; white within; hinge often slightly 

 tinged with orange and red ; margin denticulated, 

 umboes subcentral. 



LiNN^us. Systema Naturse. 

 Corbis elegans, Deshayes (var.). 

 Hab. Indian seas. 



The sculpture is coarser in the earlier portion of the 

 shell's growth than it becomes after the shell attains a 

 more mature development, when towards the ventral 

 margin the radiating ribs almost die out, and the trans- 

 verse wrinkles become finer and closer. In some 

 specimens the coarser sculpture is continued over a 

 larger portion of the surface than in others. When 

 this is the case, the name of Corbis elegans would be 

 applied to the variety so caused. It is, however, so 

 entirely a question of degree that it is impossible to 

 divide any extensive series of specimens into the two 

 species. 



Species 2. (Fig. a, b, Mus. Cuming in Brit.) 

 CoRMs SowEiUiYi. Cor. testa ventricosd, albidd. liris 

 la?miiatis extantibus concentricis, subcequidista/itibiis 

 atUice laqueatis, et striis inter liras radhtntilnis 

 ornatd, intus subaureo ; estate juniori compressii, 

 rosea radiatini fasciatd. 

 Sowerbt's CoitBis. Shell veutricose, whitish, orna- 

 mented with laminated, standing out concentric 

 ridges fluted in front and striae radiating between 

 the ridges ; within a little orange ; in the young 



banded with 



colour 



rays 



Reeve. Proc. Zool. Soc, 1841. 

 Hab. Indian seas. 



In its young state, compressed and rayed, this shell 

 bears a very strong resemblance to a fossil Corbis in 

 the Paris basin. 



November, 1872. 



