think it is," he added. "You see, my dear sir, that we are not
amusing ourselves here. I am engaged at this moment upon a monograph on
the genus duck. But I am at your disposal."

While they went towards a rather pleasant house in the Rue du Buffon,
Raphael submitted the skin to M. Lavrille's inspection.

"I know the product," said the man of science, when he had turned his
magnifying glass upon the talisman. "It used to be used for covering
boxes. The shagreen is very old. They prefer to use skate's skin
nowadays for making sheaths. This, as you are doubtless aware, is the
hide of the _raja sephen_, a Red Sea fish."

"But this, sir, since you are so exceedingly good----"

"This," the man of science interrupted, as he resumed, "this is quite
another thing; between these two shagreens, sir, there is a difference
just as wide as between sea and land, or fish and flesh. The fish's skin
is harder, however, than the skin of the land animal. This," he said, as
he indicated the talisman, "is, as you doubtless know, one of the most
curious of zoological products."

"But to proceed----" said Raphael.

"This," replied the man of science, as he flung himself down into his
armchair, "is an ass' skin, sir."

"Yes, I know," said the young man.

"A very rare variety of ass found in Persia," the naturalist continued,
"the onager of the ancients, equus asinus, the _koulan_ of the Tartars;
Pallas went out there to observe it, and has made it known to science,
for as a matter of fact the animal for a long time was believed to be
mythical. It is mentioned, as you know, in Holy Scripture; Moses forbade
that it should be coupled with its own species, and the onager is yet
more famous for the prostitutions of which it was the object, and which
are often mentioned by the prophets of the Bible. Pallas, as you know
doubtless, states in his _Act. Petrop._ tome II., that these bizarre
excesses are still devoutly believed in among the Persians and the
Nogais as a sovereign remedy for lumbago and sciatic gout. We poor
Parisians scarcely believe that. The Museum has no example of the
onager.

"What a magnificent animal!" he continued. "It is full of mystery;
its eyes are provided with a sort of burnished covering, to which the
Orientals attribute the powers of fascination; it has a glossier and
finer coat than our handsomest horses possess, striped with more or less
tawny bands, very much like the zebra's hide. There is something pliant
a