1826,] Mr. Gray on the Sea Eggs, 427 



*E. Lucuntur. Echinus, Lin, Klein, t. 30, f. A. B. **E. 

 atratus, Kleiuj t. 47, f. 12. **^E. mammillatus, Klein, t. 29, 

 f. 1. The last two sections will most probably form a new genus. 



The genus Clypeus of Klein and Leske, the Echinosinus of 

 Van Phelsum, appears to be very doubtful. Lamarck considers 

 them species of Galerites, 



2. Annectant Group. — Body not globular, variously 

 shaped; jaws not projecting; anus lateral or below; anus and 

 mouth covered with imbricate irregular scales. 



Earn. 3. Scutellidje. 



Body depressed or conical, covered with numerous minute 

 equal-sized, immersed tubercles ; spines short, conical, thin, 

 equal ; ambulacra in ten short bands bending together in pairs, 

 like the petals of a flower, formed of two distinct lateral holes 

 united by an external groove ; mouth central ; teeth blunt, not 

 exserted ; jaws formed of five pair of depressed triangular bones; 

 internal cavity divided by numerous vertical columns supporting 

 the j aws; internal oral edge with five pair of simple processes; ovarial 

 pores 4-5, situated between the ambulacra surrounding the Cor- 

 pus Spongiosum ; interovarian pores minute, at the centre of the 

 apex of the interambulacral area. 



The crustaceous covering of the body is usually thickened 

 internally by an additional coat, and, being strengthened by 

 the internal columns, resists the action of the sea for a length 

 of tirne. It is formed of twenty bands of pieces, but the conti- 

 nuation of the ambulacral bands are often very much dilated and 

 perforated. 



This family is aUied to the Echinidce by the equal spines, and 

 having jaws, &c.; to the annectant families of the order Stellerida, 

 by their jaws being only used for pressing the food, and by the 

 radiated-lobed form of some of the species. 



*Echinanthus, Bryerius. Clypeaster, Lam. 

 EcHiNANTHUs, nob, not Van FheL Echinorodum, Van 

 Phel, Scutum angulare, Klein, 



Body oval, or sub-pentangular, above convex, beneath con- 

 cave, with five grooves; ambulacra in pairs, rounded; ovarial 

 Eores five ; mouth central ; anus marginal ; the jaws, Klein, t. 33, 

 p.q. 



^Interambulacral area rounded, E. humihs, Leske, i. 1 7, f. A. 

 t. 10 B. Echinus rosaceus, Lin. E. subdepressa, nob, Klein, 

 t. 19, f. A B. Seba, iii. t. 15, f. 15 and 12. E. ambigena, scu- 

 tella. Lam. Seba, iii. t. 15, f. 13, 14. ^^'Interambulacral ; 

 area acute. E. altus, Leske, t. 53, f. 4. 



Lagan A. Placenta lagana, Klein. Echinodiscus, Van 

 Phel. not Bryerius. 



Body sub-pentangular, depressed, below rather concave^ 



