193 
OF THE LIFE OF LINNAEUS. 
« other. In vain did I, like other physicians, look for its head ; for 
« the head and mouth are in each limb or division, in some down- 
ed wards, and in others side -ways. No mortal will be able to know this 
« worm, unless he is acquainted with the nature of the Polypi , upon 
cc which so much has hitherto been written. The Taznia resembles 
st them. It is propagated by the dying limbs; and every limb is ani- 
u mated, and grows again to be a complete body.” 
As important as this discovery became to the medical world, as ad- 
vantageous proved to Linnaeus a second one, which he made in the 
same year. He found out the art of making pearls. “ I am at last 
acquainted,” says he in the same letter to Haller*, “ with the man- 
es ner in which pearls are generated in their shells. I can now ba ing 
“ it about, that each pearl-shell, (the My a Margaritifera so abun- 
«4 dandy found in the North Sea), which can be encompassed in one’s 
« hand, will, after a lapse of between five and six years, produce a 
u pearl of the size of a pea.”— He kept this secret to himself for a long 
time. In the diet of 1762, it became a subjeH of public discussion, 
and the states of Sweden , induced him, by the ofFer of a considerable 
reward to communicate it to one of their representatives, a merchant 
and direHor of the Swedish East India Company at Gothenburgh. It 
does not however appear, that any considerable benefit was ever de- 
rived from this discovery. DoQor J. E. Smith of London, the pre- 
sent proprietor of the Linn ^ean colle£lions, is also in possession of the 
manuscript which Linnaeus wrote upon the generation of pearls. This 
* Tandem intellexi, qua ratione Margarine nascantur et generentur in Conchis ; et potero 
iam efficere, ut quadibet concha margaritifera, quam licet in manu tenere, post quinque vel 
six annos ferat margaritam magnitudine seminis e vicia vulgari. ibid. 
c 
curious 
