Octomeris angulosa. 245 



Leach, Verruca, Schumacher, and Creusia Verruca, Lamarck.) 

 3rd, Balanus, (Balaiius verus Auctorum.) 4th, Chthalamus, 

 (probably the same as a part of Leach's Coniae.) 5th, Coronula, 

 (the same as Chlelonobia, Leach, and Coronula Testudinaria of 

 Lamarck,) 6th, Cetopirus, (Coronula Balaenaris, Lamarck.) 

 7th, Diadema, (Coronula Diadema, Lamarck.) 8th, Tubicinella 

 {Lamarck.) So that M. Ranzani has not actually proponed any 

 new Genus, but has only elevated several Lamarckian species to the 

 rank of genera. In the course of our work on the " Genera of Re- 

 cent and Fossil Shells," we have established one most distinct Genus 

 of the family of Pentalasmidae, namely Lithotrya, and we now pro- 

 pose to establish another, and a most distinct Genus of Balanidx, 

 It is well known, that in the Genus Balanus of all authors, the shell 

 consists of six pieces united togetiier laterally to form the cone sur?- 

 rounding the animal and operculum. The Genus Octomeris, how- 

 ever, as its name implies, consists of eight pieces united in the sanie 

 manner, to form the surrounding cone ; its resemblance to Balanus 

 will render it unnecessary for us to describe anything more than the 

 characters in which it differs from that Genus ; which are — first, 

 the character we have already mentioned ; secondly, the angular 

 internal sutures of the valves; thirdly, the foliaceous structure 

 of all the shelly parts ; fourthly, the want of an internal plate ; 

 and, lastly, a thin epidermis, which appears constantly to cover 

 this shell in its natural state, though seldom observable, because 

 the specimens are frequently covered with foreign substances. The 

 deeply sinuated and variously figured edges of the base cannot, 

 in our opinion, be considered as an essential character of the 

 Genus; but we think it probable that this Genus has no shelly 

 base, though we have never seen any specimen attached to the rockj, 

 We have given representations in our plate of the only speciei 

 we have seen of this Genus, which we have lately received fron^ 

 the Cape of Good Hope, and named Octomeris angulosa. 



Icon. Tab. nost. Suppl. Xll. 

 Fig. 1. The outside. 



2. The inside, showing tlie eight divisions. 



3. The anterior piece. 



4. The posterior piece. 



5. to 10. The lateral pieces, three on each side. 



11, The operculum, consisting ol four pieces of whicli the tw« 

 anterior are the larger. 



