68 On the Economical Uses of some species of Testacea. 
IJ. Mya marcaritirera, (Linn.)—The Horse Muscle. 
Next to the last species, this shell is the most celebrated for its 
pearls, and which in old times not unfrequently came into competi- 
tion with those from India. Julius Cesar is said to have been stim- 
ulated to the invasion of Britain by the sight of the pearls brought 
from it ;* and he certainly on his return to Rome presented a breast- 
plate made of them tothe Temple of Venus Genetrix.t They 
appear to have been at that time, A. D. 14, an object of commerce 
to Gaul, if not further south.t Forty years later they were com- 
_mon in Rome. Pliny informs us they were used in his time, and 
though of inferior worth, were often so large and beautiful as to be 
of considerable value. In general, however, they were small, dim, 
and wanting in lustre. 
About the year 1120, the Scotch pearls were in great request. 
King Alexander I. is said to have exceeded all men in that species 
of riches, and his pearls, on account of their large size and superior 
brightness were celebrated and coveted in distant countries.§ In 
1355, they were still an article of exportation. They were esteem- 
ed in France, but not equally with those of India, as appears by the 
MS. statutes of the Goldsmiths’ Company at Paris, where it is 
ordained that no worker in gold or silver shall set any Scottish pearls 
among the oriental ones, except in large jewelry for churches,|| for 
which, probably, a sufficient quantity of the oriental pearls could not 
be obtained, or were too expensive. 
Among the articles exported to Antwerp from Scotland in 1560, 
and enumerated by Guiectardin, we find “fine large pearls’ men- 
tioned. In 1665, they were still sought for and worn in England, 
and a writer in the Philosophical Transactions of London at that 
time, makes mention of one found in Ireland whieh weighed fifty six 
carats, and was valued at £40, and of another for which £80 had 
been refused, besides ‘‘ a vast number of fair, merchantable pearls, 
too good for the apothecary,” offered for sale by persons from the 
same place.** About 1760, the wearing of real pearls coming more 
into fashion, those of Scotland, which had previously been almost 
* Sueton. Vit. Jul. Cas. cap. Ixiv. 
+ Plin. Hist. Nat. lib, rx. 35. + Macpherson, I. 133. 
§ Macpherson, I. 318. ll Ibid, T. 555. 
= Macpherson, II. 131. 
** Phil. Trans, of the Royal Society, II. 831, 
