SS Mr. (irat/on the Genera of Cirrlpedeii [Aug, 



Schumacher, 1817. 



8. Malacota. Branta, Ocken. Otion, Leach, Conchoderma, 

 Olfers. Auritella, Blainv, Gymnolepas, Blain. Diet, 

 . 9. Senociita, Cineras, Leach. Gymnolepas, Blain, 



10. Tetraclita. Conia, Leach, 



11. Verruca, Clisia, Savigfij/, MSS, Ochthosia, Ranzani^ 

 Creusia, Lam. 



12. Diadema, Coronula, Leach. 

 Leach, Enci/, Brit. Sup. 1819. 



13. Acasta. Balanus, Blainv. Sow, 



14. Creusia, 



15. Pt/r^omay Savigny, MSS, Creusia, Blain, 



16. ScaTpellum, Polylepas, Blain. 



There are several other genera named by this naturalist in the 

 collection of the Museum, but they are without characters. 

 Say, Journ. Acad. N, S, Phil, 



17. Conoplea. Mesula, Leach, MSS, Balanus, Lam, 

 Sowerby, Genera, 



\%, Lithotrya, Ahsm, Leach, MSS, Litholepas, JB/<n/z. 

 Ranzani, Mem, di Stor. Nat, 



19. Chthalamus. 



20. Cetopirus, Coronula, part. Lam, 



21. Asemus. 



' This class of animah has been confounded by most authors, as 

 CJuvier, Dumeril, &c. with the Mollusca; indeed the latter first 

 separated them and the Brachiopodous Mollusca into a group 

 from the rest under the latter name, but they were very properly 

 distinguished from these animals by Lamarck, and considered 

 as a distinct group between the Annulosa and Mollusca. Latreille 

 considered them as Annelides, and Mr. W. S, Mac Leay has 

 lately pointed out their position to be an annectant group 

 between the Crustacea and the Radiata. Their affinity to the 

 former is striking ; it is not so apparent with regard to the latter, 

 but this will most likely be more obvious when they become 

 more completely known. 



Class. ClRRIPEDES. 



Lepas, Triton? Lifi. Nematopoda, Blain. Cirripoda, Lam. 

 Brachiopoda, Dumeril. Cirripeaa, Lam. Hist. 

 ' Animal. — Body soft, conical, ending in a slightly ringed tail, 

 inclosed in a fleshy sac, which is open at the hinder or anal 

 extremity. Leg;s six pair, placed on the side of the tail, each 

 ending in two compressed jointed, horny, and often ciliated 

 tippend'ages. Protected by a shelly case, formed of a certain 

 number of shelly plates, which surround the body more or less 

 completely. 



Head not distinct, eyes and tentaculanone. Nervous system 



