70 On the Economical Uses of some species of Testacea. 
mon estimate, not above one shell in one hundred might have a 
pearl, and of these pearls, not above one in one hundred might be 
round and clear, yet sufficient were found to remunerate those who 
sought for them. ‘The natives, though very foul eaters, will not 
eat the fish.” The shells which contain the best pearls are wrinkled, 
twisted and bunched, and not smooth and equal as those that have 
none ; and “ the fishermen will guess so well by the shell, that though 
watched never so closely, they will open such shells under water, 
and conceal the pearl in their mouths or otherwise.” ‘They do not 
appear to have been laid in heaps to rot as the muscle is, but opened 
and the gem extracted immediately.* 
The following ingenious mode of catching them was practiced 
about fifty years since, in the river Teith, county of Perth, Scotland, 
and we may remark, that it is the only instance we can meet with, 
where any skill or invention is obvious in the manner of fishing for 
them. A kind of spear was made use of, which was shod at the 
point with iron spoons, having their mouths inverted. The handles 
were long, elastic, and joined at the extremity, which was formed 
into a socket to receive the shaft. With this machine in his hand 
by way of a staff, the fisher, being often up to his chin in water, 
groped with his feet for the muscles, which are fixed in the mud and 
sand by one end. He pressed down these iron spoons upon the 
point, so that by the spring in the handles they opened to receive 
the muscle, held it fast, and pulled it up to the surface of the water.+ _ 
It was customary at one time for the Crown to grant patents for the 
privilege of fishing for pearls in particular streams. Sir John Haw- 
kins held a patent of this sort, and in 1633, one which had been 
granted to Robert Buchan of Auchmacoy, in the county of Aber- 
deen, was repealed by Charles the First.{ ‘There were also some 
fisheries in Saxony, which were monopolized by the government, 
but whether productive or not, we are not informed. They are 
called by the Welsh, Cregin Diluw, or deluge shells, as if they had 
been left there by the flood.$ 
lil, Pinna rorunpata? (Linn.) 
Before the introduction of the silk worm into Europe from the 
East, this shell was of much importance in the arts. The only silk 
“* Phil. Trans. I. 1 831. 
+ Sinelair’s Statistical an he of "Sigs XI. 600. t Ibid. LV. 423. 
§ Pennant’s British Zc é 
