EMARGINATED. (_e_, out; _margo_, border.) Notched or hollowed out. Applied to the edges or margins of shells, when instead of being level they are hollowed out, as the outer lip of Oliva, fig. 457, at the base, and the ventral margins of some bivalves. EMARGINULA. Lam. (_e_, out; _margo_, border.) _Fam._ Calyptracea, Lam. Branchifera, Bl.--_Descr._ Patelliform, oblong or oval; anterior margin notched or emarginated; apex posteriorly inclined; muscular impressions wide.--_Obs._ Emarginula elongata, of some Authors, PARMOPHORUS of De Blainville is commonly called the Duck's bill limpet, from its shape. The Emarginulæ may be known from Patellæ and other neighbouring genera, by the notch or slit in the anterior edge. In the genus Rimula, Defr. fig. 243, this slit is near the apex, and does not reach the margin. Recent species occur in all climates, but are not numerous. Fossil species are still more rare, occurring in the Calc-grossièr, Crag and Oolite. E. fissurata, fig. 241. ENA. Leach. A sub-genus of Bulinus. B. Lackhamensis. Mont. ENDOSIPHONITES. A genus composed of Ammonites, having the siphon close to the body whorl, fig. 476. ENDOTOMA. Rafinesque. A genus of microscopic Foraminifera. ENROULEES. Lam. See CONVOLUTÆ. ENSATELLA. Sw. A genus consisting of SOLEN ensis, Auct. fig. 60, and other species similarly curved. _Genus_ ENSIS, Schum. ENSIS. Schum. SOLEN ensis, Auct. and similar species. ENTALIS. Defr. DENTALIUM duplicatum, Bl. PHARETRIUM, König. This genus is described as a small tube, within a larger one, the smaller extremity of the inner tube projecting beyond that of the outer one. Deshayes, who describes this genus, expresses a conviction that the soft parts of the animal must be entirely different from those of the animal of Dentalium. The genus PHARETRIUM, as described by König in his "Icones Fossilium Sectiles," is evidently identical with Entalis. It is placed by him in the family of Pteropoda, but being a fossil shell, there is some difficulty in finding its place in the system. See plates, fig. 3. ENTELLITES. Fischer. A genus composed of species of TEREBRATULA, SPIRIFER, and PRODUCTUS, Auct. having the hinge large and the umbones short. ORTHIS? Dalman. ENTIRE. (Integra.) Not interrupted, not emarginated. The peritrême of a univalve shell is said to be entire when not interrupted by canals or by the body whorl. _Ex._ Cyclostoma, fig. 304. The palleal impression is entire, when continued without interruption, or without a sinus.