OCTOJWKRIS. 



and Tetraclita of Schumacher, according to De Ferussac J 

 2o Ochthosia, (the same as Clitia, Leach, Verruca, Schu- 

 macher, and Creusia Verruca, Lamarck.) 3° Balanus, 

 (Balanus verus Auctorum.) 4° Chthalamus, (probably 

 the same as a part of Leach's ConisE.) 5^ Coronula, (the 

 same as Chlelonobia, Leach, and Coronula Testudinaria of 

 Lamarck.) 6° Cetopirus, (Coronula Balsenaris, Lamarck.) 

 7*^' Diadema, (Coronula Diadema, Lamarck.) S""- Tubici- 

 nella, Lamarck.) So that Mr. 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 we have established one most distinct Genus 

 of the family of AnatiferidaB, namely Lithotrya, and we 

 now propose to establish another, and a most distinct 

 Genus of Balanidae. It is well known, that in the Genus 

 Balanus of all authors, the shell consists of six pieces 

 united together laterally to form the cone surrounding 

 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, which are — first, the character 

 we have already mentioned ; secondly, the angular inter- 

 nal 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 con- 

 stantly to cover this shell in its natural state, though sel- 

 dom observable, because the species are frequently covered 

 with foreign substances. The deeply sinuated and vari- 

 ously 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 representation 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. 



Fig. 1. The outside. 



2. The inside, showing the eight divisions. 



3. The anterior piece. 



4. The posterior piece. 



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



1 1 . The operculum, consisting of four pieces of which the two aniterior 

 are the larger. 



