404 



DONACIN^. 



radiato-striate or decussate, covered with an epidermis; inner 

 margin of valves entire, or crenulated. Hinge composed of 

 two cardinal teeth in one valve, and one bifid tooth in the 

 other ; one, or two lateral teeth in each valve ; ligament 

 short, external. Muscular impressions rounded or oblong ; 

 pallial sinus wide and deep. 



Syn. Chione, Scop. Donaciarius, Bum. Egeria, Lea, 

 not Roissy. 



Ex. T>. venustus, Poli, pi. 104, fig. 5. Shell, D. rugosus, 

 Linnceus, fig. 5, , 5, b. 



The mantle in Donax is fringed at the margin, the siphons 

 are short, thick, and diverging, the anal orifice is denticulated, 

 the siphonal furnished with pinnate cirrhi, and the labial 

 palps are small and pointed. The Donaces inhabit the sandy 

 shores of all tropical countries; a few species are also 

 from Northern Coasts, and several are natives of the British 

 Islands ; they are usually found buried a few inches beneath 

 the surface, near low-water mark. 



Species of Donax. 



acuminatus, Desh. 

 assitnilis, HanJey. 

 Cayennensis, Lam. 

 clathratus, Desh. 

 consanguineus, C.B. Adams. 

 denticulatus, Linn. 

 Dysoni, Desh. 

 flexuosus, Gould. 

 granifer, Desh. 

 Hanleyanus, Phil. 

 incarnatus, Chem. 



introradiatus, Reeve. 

 laevigatas, Desh. 

 lubricus, Hanley. 

 Madagascariensis, Wood. 

 obesus, D'Orh. 

 obsesulus, Desh. 

 paxillus, Reeve. 

 rugosus, Linn. 

 semisulcatus, Hanley. 

 sordid us, Reeve. 



