240 



It is doubtful whether there are more than one specimen of this genus. 

 This shell has not, to my knowledge, been found fossil. 



CLIX. Coronula. A regular subrotund, or subconical shell, divided 

 into twelve areae, with an opening both in the superior and inferior part; 

 that in the superior part closed by a four-valved operculum. 



Of this genus there appears to be three species known, which may 

 be distinguished by the same specific names which distinguished them 

 under the genus Balanus : C. diadema, C. testudinarius, and C. bala- 

 naris. 



The shells of these two genera, with their inhabitants, are found deeply 

 imbedded in the fat of the whale, so as to leave only the superior surface 

 uncovered. M. Dufresne, who first gave this information to Lamarck, 

 obtained it upon viewing two specimens, preserved in the collection of 

 Mr. John Hunter, in which several of the genus Tubicinella, and of the 

 species Cornonula baleanaris, were thus fixed in part of a whale. M. Du- 

 fresne was led by the knowledge thus obtained, to repair to Greenland 

 Dock, to inquire of persons concerned in the whale-fishery, what they 

 had observed respecting these animals. He was there assured, by a per- 

 son of the name of Palmer, that he had caught a whale which carried 

 more than two hundred of these animals, arranged in groups of twelve 

 or fifteen families or tribes, on the superior part of the whale. Ann. du 

 Mus. i. 170. 



Whilst placing before you a representation of a rare and unexpected 

 fossil, Coronulites diadema, Plate XVI. Fig. 19, I much regret at not being 

 able to inform you where it was found. A view of the figure will show you 

 its agreement with Gmelin's description of Lepas diadema, Linn, which, 

 in the words of Linnaeus himself is, Testa subrotunda, sex lobata sulcata. 

 Gmelin says of it : Habitat , sordide alba, I pollicis circiter alia, sursum 

 angustior, apertura superiori infundibiliformi, dimidiam reliqute testa diame- 

 trum aguante, areis exterius 12 triangulis, quorum 6 excavate striis subtilibus 

 transversis exarata, sex alters elevata 4-5-6 prominentiis arete sibi accumbentibus, 

 et striis transversis crenatis exaratis constant. Syst. Natura, p. 3208. I know 



