VENUS. 



Plate I. 



Genus VENUS, Li/mieiis. 



Tc'/sla aubtriyuno-ovala, vel orbicularis, craasiusculu, seepis- 

 niixt; tiiryida, conceidrice lirata vel laminata, intcr- 

 dmu, auiem raro, radiatini lirata vet striata, ad mar- 

 gines pteriimque crenulalu. Cardo incrassat/is, in 

 nlrdqiie valvri trideiitatus, deniibim cardinalibiis, di- 

 vergaitibm, inlerdum bifidis. Imprcssio pallii postici; 

 sinuoso, sinu hreviusculo. 

 Shell soiuewliat trianji'iiliirly ovate or orbicular, rather 

 thick, most frequently turgid, concentrically ridged 

 or laminated, sometimes, but seldom, radiately 

 ridged or striated, generally crennlated at the mar- 

 gins. Hinge thickened, three-toothed in each valve, 

 teeth cardinal, diverging, sometimes bifid. Impres- 

 sion of the mantle sinuated posteriorly, sinus rather 

 short. 

 The species referred to this genus are couspicuously 

 distinguished from the rest of the family by their elaborate 

 sculpture of concentric ridges variously developed in cre- 

 nnlated and reflected laminae, sometimes crossed in the in- 

 terstices with radiating strife, and by their turgid growth. 

 They are about equally distributed in the two hemispheres, 

 in one chietly on the west coast of America, especially 

 Central America, and the West Indies, in the other chiefly 

 among the Philippine Islands, Australia, and New Zea- 

 land. Seven species inhabit European seas, of which five 

 are natives of our own shores. The laminated species, of 

 which the beautiful Tasmanian V.lamellata, the V.pti- 

 cata, papilla, tliiara, and others are characteristic examples, 

 are separated, however, by some authors under the generic 

 name of Cldone. The United States possess a very large 

 species, V. mercenaria, which has been subdivided into 

 four species, and then set apart as a genus of itself. A 

 genus has also been made. Gemma, of a small pellucid 

 species, which inhabits the same locality, and has been 

 regarded as the fry of V. mercenaria. Lastly a small group 

 of hnlf-a-dozen species, of a peculiar flexuous form, in- 

 habiting the West Indies and Central America, have been 

 raised somewhat unnecessarily, for the animal is not known, 

 to the rank of a separate genus, with the name Anomalo- 

 cardla. 



The Veneres are not remarkable for colour. A few of 

 the species, chiefly those referred to Chione, are gaily 

 painted, but the predominant tone is fulvous cream- 

 colour, more or less indistinctly marked with rust-brown. 



Species 1. (Mus. Cuming.) 



Venus oblonga. T'en. testa oblonyo-ovatd, suboljliqiid, 

 valde inreqnilaterali, siibdepresse convexd, sqiialidi 

 fiisctscente-albd, co/icentrice dense lawellalo-lirat/l, 

 liris pins minus rejlexls. 



The oblong Venus. Shell oblong-ovate, rather ob- 

 lique, very inequilateral, rather depressly convex, 

 dull fuscous-white, concentrically densely lamelhitcly 

 ridged, ridges more or less reflected. 



Venus oblonga, Hanley, Ind. Test. Supp. pi. 1(3. f. 1. 

 J'enus Zelandica, Gray. 



Hub. New Zealand. 



Varying occasionally in form in being more or h'ss 

 convex and lamellated, but always of the same dull colour- 

 less hue. 



Species 2. (Pig. a, b, Mus. Cuming.) 



Venus lima. Ven. testa pectinato-ovatd, albidd, anrantio- 

 fusco sparsim variegatd, radiatim rnodice costatd, 

 costis rotiindatis, iinbricalo-squaniutis, lunula fiiho- 

 fuscescente. 



The file Venus. Shell pectinately ovate, whitish, 

 sparingly variegated with orange-brown, radiately 

 moderately ribbetl, ribs rounded, indiricately scaled, 

 lunule fulvous-brown. 



Tupes lima, Sowerby, Thes. Conch, vol. i. p. tiOS. pi. 151. 

 f. 144. 

 Chione lima, Deshayes. 



Ilab. New Zealand. 



A scabrous radiately-ribbed species belonging to the 

 pectinate division of the genus. 



Species 3. (Mus. Cuming.) 



Venus clathkata. Ven. testa cordato-ovatd, siibobliqud, 

 crassd, ventricosd, laded, rufescente-spadiceo pattide 

 maculatd et radiatd, concentrice dense lirata, tins 

 irregularibus, prope umbones tenuibus, delude cal- 

 lusis et planatis, sulcis Unearibus radiantibus uu- 

 dique clathratis, liris ad aream posticayn. serrato-htuii- 

 natis. 



The latticed Venus. Shell cordately ovate, ratlicr 



Februnrv, 18G4. 



