44 LEPAS. 



SMOOTH ACORN. 

 PL 7. /. 1. 



11. Lepas balanoides. L. testa conica truncata Icuvi, operculis obtusis. 



Linn. Syst. Nat. p. 1 108. Linn. Gmel. p. 3207. 

 Shell conical, truncated, smooth : operculum obtuse. 

 Balanus, testa subcylindrica laevigata; apertura dilatata; radiis in- 



sculptis Icevibus. Brug. Encyclop. Method. Hist. Nat. torn. 6. p. 164. 

 Lister, Conch, t. 444. f. 287. Chem. Conch. 8. t. 97. f. 826. and~m. 



f. 833. Penn. Brit. Zool. ed. 1812. 4. t. 40. f. 2. Da Costa, Brit. 



Conch, p. 248. t. 17. f. 7. Donov. Br. Shells, t. 36. f. 2, 3. Mont. 



Test. Brit. p. 7. Linn. Trans. 8. p. 24. 



A much smoother shell than the preceding : the com- 

 partments divided by a longitudinal furrow; and the 

 valves sometimes deeply sulcated at the base : points of 

 the valves generally directed one way, and ending in a 

 beak. Operculum of four valves, the two upper of 

 which are slightly striated, transversely, the others are 

 quite smooth. Colour whitish. Size, at the base, from 

 one quarter to three quarters of an inch ; height, from a 

 quarter to half an inch. 



This is a very common shell on rocky coasts, and is 

 found in abundance adhering to almost every fixed 

 substance between high and low water mark. It occurs 

 generally in clusters, and is frequent on oyster and other 

 shells, and on the back of lobsters. It inhabits Europe, 

 America, and India ; and, if looked for, will most pro- 

 bably be found also on the coast of Africa. 



The shell represented by Chemnitz, in vol. 8. pi. 97. 

 f. 824. is a remarkable variety of the L. balanoides, 

 The author has a specimen nearly like it, seated on the 

 back of the Nerita Catena, but it has not quite so much 

 of the tulip shape. 



