Here we halted, and while Challoner recovered his breath, I looked round on the familiar scene.  The inevitable whale’s skeleton—­a small sperm whale—­hung from the ceiling, on massive iron supports.  The side of the room nearest the door was occupied by a long glass case filled with skeletons of animals, all diseased, deformed or abnormal.  On the floor-space under the whale stood the skeletons of a camel and an aurochs.  The camel was affected with rickets and the aurochs had multiple exostoses or bony tumors.  At one end of the room was a large case of skulls, all deformed or asymmetrical; at the other stood a long table and a chest of shallow drawers; while the remaining long side of the room was filled from end to end by a glass case about eight feet high containing a number of human skeletons, each neatly articulated and standing on its own pedestal.

Now, this long case had always been somewhat of a mystery to me.  Its contents differed from the other specimens in two respects.  First, whereas all the other skeletons and the skulls bore full descriptive labels, these human skeletons were distinguished merely by a number and a date on the pedestal; and, second, whereas all the other specimens illustrated some disease or deformity, these were, apparently, quite normal or showed only some trifling abnormality.  They were beautifully prepared and bleached to ivory whiteness, but otherwise they were of no interest, and I could never understand Challoner’s object in accumulating such a number of duplicate specimens.

“You think you know this collection inside out,” said Challoner, as if reading my thoughts.

“I know it pretty well, I think,” was my reply.

“You don’t know it at all,” he rejoined.

“Oh, come!” I said.  “I could write a catalogue of it from memory.”

Challoner laughed.  “My dear fellow,” said he, “you have never seen the real gems of the collection.  I am going to show them to you now.”

He passed his arm through mine and we walked slowly up the long room; and as we went, he glanced in at the skeletons in the great case with a faint and very horrible smile on his bloated face.  At the extreme end I stopped him and pointed to the last skeleton in the case.

“I want you to explain to me, Challoner, why you have distinguished this one by a different pedestal from the others.”

As I spoke, I ran my eye along the row of gaunt shapes that filled the great case.  Each skeleton stood on a pedestal of ebonized wood on which was a number and a date painted in white, excepting the end one, the pedestal of which was coated with scarlet enamel and the number and date on it in gold lettering.

“That specimen,” said Challoner, thoughtfully, “is the last of the flock.  It made the collection complete.  So I marked it with a distinctive pedestal.  You will understand all about it when you take over.  Now come and look at my gems.”