7 
testaceous plate. The opening on the top closed by four 
Moveable valves, inserted near tlio base of the inside of 
, the shell. 
B COMMUNIS. Lepas Bilanus. Turt. Lin. L. Cor- 
nubiensis. Pen. Brit. Zo., vol. 4, pi. 37, fig. 6. B. C. 
Mont. Test. Brit., vol. 1, p. 66. Stew. Elem., vol. p. 363. 
4 Acorn shell. Common on rooks ; clustering. 
B - BALANOIDES. Lepas B. Turt. Lin. Pen. Brit. 
Zo., vol. 4, pi. 37, fig. 5. Stew. Elem., vol. 2, p. 364, 
B - B. Mont. Test. Brit., vol. 1, p. 7. Covering rocks, 
multitudes. 
B - PUNCTATUS. Mont. Test. Brit., vol. 1, p. 8, and 
Pl» 1, fig. 5. This has generally been confounded with the 
preceding: a circumstance not surprizing, from the little 
attention hitherto paid to these animals, and the difference 
°f their form from variety of position, clustering and age. 
TINTINNABULUM/ Mont. Test. Brit., vol. 1, p. 10. 
.Montagu describes this shell from specimens attached to 
bottoms of ships from warm climates ; but doubts of its 
eiQ g a native of our seas. I have found numerous speci- 
..' eQ s, answering to his description in all but size, attached to 
le surface of the Nidus of Bnccinum Undatum, thrown on 
j ° r e on the beach, and consequently from no great distance 
j. 1 the ocean. A comparison of these specimens, scarcely a 
in diameter, with the foreign shells, which are among 
e largest of the genus, may lead to a suspicion that they 
a e not certainly identical ; in which case the Cornish will be 
'rj,n®w species ; but this must be left for further investigation. 
ne colour of this shell is pure white ; of the inner valves 
P'Mple. 
fw ACASTA. 
ERIC CHARACTER: The shell sessile, oval, sub- 
c onic; formed of separable pieces, forming six unequal 
Plates ; the bottom a convex plate externally. Cover with 
. mnr valves. 
■ MONTAGUI. Crouch’s Introduction to Lamark’s 
^ opchology, pi. I, fig. 15. This species does not fix on 
£ 'd bodies, but lives embedded in spoDge. It is obtained 
10, n deep water, and is scarcely common. 
q Pi . t CREUSIA. 
jvY® RIC CHARACTER: The shell sessile, fixed, or- 
, Malar, with four plates, which are unequal, united by 
* ptjnct sutures. Cover internal, with four valves. 
• STRIATA. Lepas Intertexta. Turt. Lin. L. Striata. 
£ en - Brit. Zo., vol. 4, pi. 38, fig. 7. Balanus S. Mont. 
p 6 .jp Bri, -» V °I. 1 P- T2. L. S. Stew. Elem., vol. 2, 
Common on shells, rocks, and the stalks of sea- 
w ^ e re not often uncovered by the tide : clustering, 
not so as to influence the regularity of growth. 
