LEPAS. 65 



DUCK BARNACLE. 

 PL 11. Mr. Sowerby. 



37. Lepas anatifera. L. testa subtriangvlari, quinquevalvi, Itevi, pedun- 



culo longo insidente. Linn. Syst. Nat. ed. 12. p. 1109. Linn. 



Gmel. p. 3211. 

 Shell subtriangular, of five smooth valves, seated on a long foot stalk. 

 Anatifa laevis. Brug. Encycl. Meth. Hist. Nat. torn. 6. p. 62. 

 Gualt. Test. t. 26. f. E. Seba Mus. 3. t. 16. f. 1, 2. Knorr. Vergn. 2. 



1. 30. f. 4, 5. Ellis, Phil. Trans, vol. 50. t. 34. f. 5. 6. Muller, 



Vollst. Natur. Syst. torn. 6. pi. 10. f. 8. Da Costa, Brit. Conch, pi. 



17. f. 3. Penn. Brit. Zool. ed. 1812. vol. 4. pi. 41. Chemn. Conch. 



8. pi. 853—855. Encyclop. Method, pi. 166. f. 1. Donovan, Brit. 



Shells, pi. 7. Mont. Test. Brit. p. 15. Linn. Trans. 8. p. 28. 



A bluish white shell with five valves, four of which 

 are faintly striated ; the fifth, or dorsal valve, is smooth 

 down the middle, and sulcated at the sides. It differs 

 principally from the preceding species, or L. anserifera, 

 in the large valves, which are not sharply carinated, as 

 in that shell ; in the superior valves, which are trun- 

 cated at the apex ; and in the striae, which are much 

 fainter in the L: anatifera. These shells are found in 

 considerable clusters, from half an inch to an inch and 

 three quarters in length, and more than an inch in 

 extreme breadth. They are seated on a flexible pedi- 

 cle, which is sometimes a foot long. The specimen 

 figured in pi. 11. was, among many others, alive in a 

 tub of sea water, and had a cluster of young ones 

 branching from its side. The drawing was made while 

 the animals were extending their plumose tentacula in 

 search of food, and while the orange colour of the 

 membrane which lines the valves, and which is often 

 lost in drying, was in all its beauty. The pedicle was 



VOL. I. f 



