Octomeris angulosa. 245 



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

 3rd, Balanus, (Balanus varus 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 proposed 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 Ave now pro- 

 pose to establish another, and a most distinct Genus of Balanidas. 

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

 consists of six pieces united together 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 same 

 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 ; Avhich 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 rock. 

 We have given representations in our plate of the only species 

 we have seen of this Genus, which we have lately received from 

 the Cape of Good Hope, and named Octomeris angulosa. 



Icon. Tab. nasi. Suppl. XII. 



Fig. 1. The outside. 



2. The inside, showing the eight divisions. 



3. The anterior piece. 



4. The posterior piece. 



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

 11. The operculum, consisting of four pieces of which the two 

 anterior arc the larger. 



