380 MURICIDiE. 



ranged three in a row, the middle or axile one broadly 

 quadrate and tridentate, the laterals claw-shaped ; jaws 

 linear, corneous. Mantle lax, produced into a short 

 siphon, which is rarely projected far beyond the canal of 

 the shell. Branchial plumes, two. Male organ curved, 

 linear lanceolate, reflected. Foot ovate, oblong, or sub- 

 quadrate, posteriorly obtuse, anteriorly emarginate. 



The species of this genus, like many other Mollusks of 

 the family, secrete a fluid which, when exposed to the air, 

 becomes of a rich purple ; and the name Purpura.) applied 

 by the ancients to Miirex truncidiis^ the creature that 

 furnished the famous Tyrian dye, was assigned by the 

 moderns to the generic group now under consideration. 

 Much interesting information on the subject of the purple 

 fluid and its sources, will be found by the reader in Dr. 

 Johnston's delightful Introduction to Conchology. 



P. LAPiLLus, Linnaeus. 



Plate CII. fig. 1, 2, 3, and (Animal) Plate L L. fig. 4. 



Lister, Anim. Angl. pi. 3, f. 5, 6 ; Hist. Conch, pi. 965, f. 18, 1,0. — Knorr, 



Delices dcs Yeux, vol. vi. pi. 29, f. 4. 

 Buccinum lapiUus, Linn. Syst. Nat. ed. 12, p. 1202. — Penn. Brit. Zool. ed. 4, 

 vol. iv. p. 119, pi. 72, f. 89. — Pulteney, Hutchins, Hist. 

 Dorset, p. 41. — Donov. Brit. Shells, vol. i. pi. 11. — Mont. 

 Test. Brit. vol. i. p. 239 ; Suppl. p. 104. — Maton and 

 Rack. Trans. Linn. Sec. vol. viii. p. 135. — Rack. Dorset 

 Catalog, p. 44, pi. 15, f. 1 to 4, 9, 12. — Turt. Conch. 

 Diction, p. 14. — Brookes, Introd. Conch, f. 78. — Dillw. 

 Recent Shells, vol. ii. p. 613. — Wood, Index Testaceolog. 

 pi. 23, f. 62. 

 Utriculiis, 4c Martini, Conch. Cab. vol. iii. p. 428, pi. 121, f. 1111, 1112 ; 



p. 433, pi. 121, f. 1113, 1114. 

 Buccinitm cunalicuhdam jv/rpuro-buccinum, Da Costa, Brit. Conch, p. 125, pi. 7, 



f. 1 to 4, 9, 12. 

 Xassa, hiiccinuin, lapiUus, n^-c. Chemnitz, Concii. Cab. vol. iv. pi. 122, f. 1128, 

 1129. 



