LEPAS. 71 
A. With the valves connected by a cartilage, and at- 
lacked to a fleshy stalk. Barnacle, 1 to 7- 
B. Firmly fixed, without stalk, conical, with an inter¬ 
nal lid. Acorn-shell, 8 to 20. 
» 1. Lepas anatifera. Duck Barnacle. 
Pennant, pi. *41, upper figures— Da Costa, pi. 17- f. 3— 
Donovan , pi. 7— Wood, pi. 11— Dorset Cat. pi. 2. f. 3. 
Shell flattish, with five blueish valves connected by a 
yellow membrane; the two lower-ones large, somewhat 
triangular, slightly wrinkled longitudinally, and obscurely 
striate in a radiate manner from the lower angle on the 
anterior side ; the two top ones not half the size, long and 
tapering down to a rather obtuse point, angular on each 
side towards the upper part, and longitudinally striate 
the back-valve long, narrow, rounded on the back, tapering 
towards the ends/eurved, striate longitudinally, and ter¬ 
minating towards the bottom in a kind of ridge: stalk long, 
transparent, horn-color, growing darker and more opake 
and wrinkled towards the shell, rarely red : length above 
aninch and a half; breadth an inch. 
Variety A. The back valve appearing as if separated into 
several distinct joints. 
Variety B. The back valve strongly ribbed longitudi¬ 
nally at the sides on the lower purt, and the ribs closely 
tuberded. 
Variety C. The back valve, with a longitudinal row of 
obtuse tubercular denticles. 
Uster, pi. 439. f. 282, left hand figure. 
Variety D. The back valve deeply and sharply serrated. 
j %22. 
Lepas dentata. Wood , p. 67— DiUioyn, p. 32. 
These several varieties presented themselves to us among 
the vast mass which floated into the river Ex, in Devon- 
dure, in the summer of 181/. And as the other parts of 
the shell and its appendages were in every respect similar 
to L. anatifera, we cannot consider any of them as entitled, 
to specific distinction. - 
On drifted timber, and the bottoms of ships. 
2. Lepas 
