24 



will also serve to convey a satisfactory idea of the general form of this 

 species, a small specimen of a perfect cast is represented Plate II. Fig. 8, 

 from Malta. 



Scutum altum, vcl Echinanthus altus, has only yet been met with in a petri- 

 fied state. It differs from the former species in heing higher, and having 

 wider ambulacra. Figures of it have been given by Scilla, t. ix. /. 1,2; 

 Bonan. Nat. Hist. t. xxxvi. /. 1 ; by Mercatus, Met. Mm. p. 233 ; and 

 by Leske, Tab. LIU. 4. A specimen of this fossil, which I possess, may, 

 I think, be considered as a variety from those which have been figured 

 by the above authors. Although equally high, its sides rise not so sud- 

 denly, but more obliquely, to the vertex ; forming, therefore, a more 

 acute angle with the base. I obtained, at the sale of the Leverian Mu- 

 seum, a complete specimen, being the nucleus of the echinite of the 

 above authors : it serves to give a correct notion of the structure, as well as 

 of the form of this echinite. PI. IV. Fig. 7. 



Scutum ovatum, vel Echinanthus ova/us. The fossils comprised under this 

 species of Leske, differ so considerably in form from the preceding, as 

 seems fully to authorize their separation into two genera. The difference 

 which is discoverable between different specimens of the oval scuta 

 appear, also, to be such, as would fully warrant the separating of them, 

 with Klein, into species, instead of into varieties, as has been done by 

 Leske. Fossils of this form are figured by Aldrovandus, Mus. Met. p. 498, 

 /. 1, 2; Mercatus, Mus. Metal, p. 232; Rumphius, D* Amboiiische Rar. 

 R. LIX. /. D. ; and others. The one which is here represented, from 

 Verona, Plate II. Fig. 5, is interesting on account of the distortion of its 

 figure, and particularly of one of its rays. 



Leske regards as a doubtful species, Echinanthites orbicular is, since the 

 specimen from which he forms his species, and which is taken from one 

 of Knorr's plates, Monumens des Catastrophes, T. u. Tab. E. in. Fig. 3, 

 is too imperfect to give a correct knowledge of its characters. 



The fossil, Plate II. Fig. 2, is, I believe, of this species, and has hardly 



