M I T R A Episcopalis. 



Family Volutirlae. — Sub-Family Mitrianae. 



Generic Character. 



Animal 



Shell never tunitecl or plaited, ovate-fusiform, the base vvide, ob- 

 tuse, and truncated: pillar with 4 plaits: the plaits simple. 

 Outer lip crenulated, or toothed : Aperture at the base etiuse, 

 smooth within, and destitute of an internal groove. Nobis. 

 Types of Form. 

 1, ni. episcopalis. 2, papalis. 3, scabriuscula : A, Zebra. 5, 

 ferruginea. 



Specific Character. 



Shell with the spire thickened, and marked by transverse punctured 

 dots: iL'hite ivith crimson spots; inferior spots small and 

 quadrate, the superior large and irregular ; pillar 4 plaited. 



Voluta vel Mitra episcopalis, Auct- (Lam. Syst. 7. 299.) 



We view this elegant, though common shell, as the type of 

 the Lamarkean Mitres, a group we shall hereafter consider 

 as a sub-family. It is common in various parts of the Asiatic 

 Ocean, and sometimes occurs of gigantic size : in its natu- 

 ral state it is covered with a thin olive epidermis. 



We regret that the nature of this work will not permit 

 us to do more than furnish the clue, to the natural 

 arrangement of the two typical groups of this family, 

 Voluta and Mitra. The first of these we have, indeed, 

 pledged ourselves to enter upon more fully in Exotic Con- 

 chology. But the arrangement of the Volutes is so inti- 

 mately connected with that of the Mitres, that we scarcely 

 know how to illustrate one, without perpetually adverting 

 to the other. 



The two typical groups of the Lamarkian Mitrse we now 

 characterise from their shells ; they correspond to those of 

 the typical Volutes ; while their internal relations may be 

 learned from the respective types of form here designated. 

 The genera Mitra and Tiara, each present a circular 

 series of affinities, and are united by the fourth type in 

 each group. Even a partial study of this disposition will 

 reveal to the Conchologist a harmony of design, amid the 

 greatest diversity of structure, which he could scarcely have 

 suspected in the mere covering of an animal. 



The shells which appear associated with M. episcopalis, 

 in this type of form, are never coronated : the only external 

 sculpture which they in general possess, are delicate rows 

 of minute punctured dots, in the typical examples, as Per- 

 tusa, millipora, versicolor, the outer lip is acutely toothed ; 

 while in the aberrant species, Melamana, tesseltata, scutu- 

 lata, &.C. this part is smooth. 

 Mitranae, PI. 4. 



