Manchester Memoirs, Vol. Ix. (191 6), No. 7. 5 



of Bristol, in 1686, 3 who conducted experiments on shell- 

 fish (Purpura lapillus) found on the shores of Somerset- 

 shire, South Wales, and Ireland, in the course of which he 

 discovered the curious photogenetic properties of the 

 colour. These experiments were continued by other 

 observers, including Reaumur, 4 du Hamel/ 5 Deshayes, 6 and 

 Lacaze-Duthiers. 7 The general concensus of opinion on 

 the question is that the ' purpura ' of Pliny is the Murex 

 trunculus, or the M. branderis, of modern conchologists, 

 while the ' buccinum ' of the Roman naturalist is probably 

 the Purpura hcemastoma, all three species being common 

 to the Mediterranean shores. The Purpura lapillus^ so 

 abundant on the shores of Europe generally, is also likely 

 to have been employed in the production of the inferior 

 sort of purple. 



The Murex-sheW is almost constantly in evidence as 

 a design upon Tyrian coins from A.D. 112 onwards. The 

 shell here is quite distinct from the " so-called " Murex of 

 pre-Alexandrine coins (circa 450-400 B.C.). The latter is 

 not a Murex at all, but is more like a Triton, or trumpet- 

 shell ; and the same shell appears on the coins of Byblus 

 (c. 350 B.C.) and of Tarentum (V. 400-330 B.C.). The 

 Murex of the imperial coins of Trye (A.D. 112 on) is 

 distinctly like Murex branderis, one of the chief purple- 

 yielding shells. 



Whether the design of the Murex (and so-called 

 Murex) on these coins had primarily any connection with 



z Phil. Trans. Roy. Soc, Loud., xv. , pp. 278 — 86, and plate. 



4 Mini de P Acad, des Sciences, 171 1, pp. 168-199 (Reaumur also 

 accidentally discovered that the egg-capsules of Purpura afforded the dye 

 in greater abundance, and with less trouble, than the animal itself). 



5 Ibid. 1736, pp. 49-68. 



G " Mollusques de la Mediterranee," in "V Exped. Scient. de More'e, 

 Section des Sciences physiques," iii., Paris, 1832, pp. 189-192. 



7 Proc. Roy. Soc. Loud., x., i860, pp, 579-584; also Ann. des Set. 

 A r at. Z00L, xii., 1859, pp. 5-84, and plate. 



