He went to the door, and returned carrying a letter, the envelope of
which he was closely examining.

"You can find out from who it is by opening it," suggested Jerry.

"Here's a funny thing," spoke Ned. "This letter is addressed to my
father, but, down in one corner it says, 'May be opened by Ned, in
case of necessity.'"

"Well, then, open it," suggested Bob. "This is a case of necessity.
Where's it from?"

"Boston, but I don't recognize the writing."

"Open it," called Jerry.

Ned did so, and, as he read, he uttered a cry of astonishment.

"Well if this isn't a queer thing," he said. "Did you ever see such a
coincidence? This letter is from Professor Uriah Snodgrass, and listen
to what he says: 'Dear Mr. Slade, or Ned. I write thus as I want one
of you to read it in a hurry, and one of you may be away from home.
You remember the last I saw of you and your chums (this part is for
Ned) was in Florida. There I secured the rare butterfly I was looking
for, and, through that success I was able to obtain a position with a
Boston museum, to travel all over the world for them, collecting
valuable specimens. I have been here for only a few weeks, but I
already have a commission. I am soon to start for California, in
search of a Cornu batrachian.'"