24 
BIOGRAPHICAL SKETCH OE 
to be met with, except on the bones and feathers from a 
particular species of raven. Among trees, the fir, the 
poplar, the oak and the birch, are peculiarly marked by 
the variety and abundance of these parasitic genera. 
They not unfrequently occur in the interior of the 
trunks of timber-trees. Mr. Schweinitz had in his col¬ 
lection, fine specimens of the Dematium aluta , taken 
out of the ships of war built by our government, on 
Lake Erie, where, in a few years, he remarks, (( this little 
fungulous enemy completely destroyed that fleet which 
had so signally vanquished the armament of Britain.” 
It was remarked by the cynic of old, when a pamper¬ 
ed mouse had perched himself on a corner of his table, 
awaiting the eleemosynary crumb which the habit of 
intimacy between the two individuals had taught him 
to expect, that even Diogenes, too, had his parasites . 
If it be true, that all men, how T ever humble, have their 
appropriate adherents-—}!ow much more so, when we 
descend to the inferior orders of creation? Scarcely, 
it is believed, can a species of animals, whether they in¬ 
habit air, earth, or ocean ;—whether they proudly soar 
or lowly creep, be found, unattended by those which 
occupy, in regard to them, a parasitic character. 
It will be remembered that in one of the papers of 
our late lamented Say, the parasitic insect, which 
feeds upon the Hessian fly is described. The study of 
cryptogamic botany makes known innumerable exam¬ 
ples of the same general fact, in regard to that great 
department of nature’s works. 
In the synopsis of the 66 Fungi of Lusatia,” the authors 
