Geographical Distribution of the Shell-Purple Industry. 2% 
DrArcenvilley im his\*Conchyliologie (1742, p. 181), 
states that the “ Conque Persique” is made use of both tn 
Panama and Guatemala for dyeing purposes and, on that 
account, is called “ Poupre de Panama.” The “Conque 
Persique ” (Purpura perszca) inhabits the Indian Ocean, 
and was distinguished from the Purpura patula of the 
Pacific coast by Brugicre in 1789 and Lamarck in 1803. 
In 1744, Don Antonio de Ulloa saw at S. Elena, in 
what is now Ecuador, and also at Nicoya (Costa Rica), 
purple colour produced from sea-shells. He describes the 
process in his “Physical and Historical Account of 
Southern and North-Eastern America” as follows: “On 
the coasts belonging to the province of Guayaquil the 
finest: purple is found. The animals from which it is 
derived are contained in shells, about the size of walnuts, 
and live on rocks washed by the sea. They contain a 
juice or humour, which is taken out, and yields the true 
purple... . . Cotton, thread, and other delicate materials 
are dyed with it. It gives a lively and durable colour, 
which does not lose its lustre by frequent washings, but 
is rather improved thereby, and does not fade through 
long-continued use and exposure. Near the port of 
Nicoya in the province of Guatemala the same kind of 
shell-fish is found, and is used for dyeing cotton. 
Various processes are employed for extracting the juice 
or humour. Some kill the animal. They take it out of 
its shell, and, having laid it on the back of the hand, press 
and squeeze it with a knife from the head to the tail, and 
then separate the expressed juice, the rest of the animal 
matter being thrown away. They treat in this way a 
number of animals until they have a sufficient quantity 
of juice. They then draw through the thread which they 
wish! to dye, and mo more is required. .... Others 
express the juice without killing the animal. They do 
