“Are you going to spoil what you cannot replace?” The retort was swift, almost fierce.

“Surely, you won’t blame me if he looks beyond this horizon,” protested Io.  “Life is sure to reach out in one form or another and seize on him.  I told him so.”

“Yes,” breathed the other.  “You would.”

“What were you intending to do with him?”

There was a hint of challenge in the slight emphasis given to the query.

“I?  Nothing.  He is under no obligation to me.”

“There you and he differ.  He regards you as an infallible mentor.”  A twinkle of malice crept into the slumbrous eyes.  “Why do you let him wear made-up bow ties?” demanded Io.

“What does it matter?”

“Out here, nothing.  But elsewhere—­well, it does define a man, doesn’t it?”

“Undoubtedly.  I’ve never gone into it with him.”

“I wonder if I could guess why.”

“Very likely.  You seem preternaturally acute in these matters.”

“Is it because the Sears-Roebuck mail-order double-bow knot in polka-dot pattern stands as a sign of pristine innocence?”

In spite of herself Miss Van Arsdale laughed.  “Something of that sort.”

Io’s soft lips straightened.  “It’s rotten bad form.  Why shouldn’t he be right?  It’s so easy.  Just a hint—­”

“From you?”

“From either of us.  Yes; from me, if you like.”

“It’s quite an intimate interest, isn’t it?”

“‘But never can battle of men compare With merciless feminine fray’”—­ quoted Io pensively.

“Kipling is a sophomore about women,” retorted Miss Van Arsdale.  “We’re not going to quarrel over Errol Banneker.  The odds are too unfair.”

“Unfair?” queried Io, with a delicate lift of brow.

“Don’t misunderstand me.  I know that whatever you do will be within the rules of the game.  That’s the touchstone of honor of your kind.”

“Isn’t it good enough?  It ought to be, for it’s about the only one most of us have.”  Io laughed.  “We’re becoming very serious.  May I take the pony?”

“Yes.  Will you be back for supper?”

“Of course.  Shall I bring the paragon?”

“If you wish.”

Outside the gaunt box of the station, Io, from the saddle sent forth her resonant, young call: 

“Oh, Ban!”

“’Tis the voice of the Butterfly; hear her declare, ’I’ve come down to the earth; I am tired of the air’”

chanted Banneker’s voice in cheerful paraphrase.  “Light and preen your wings, Butterfly.”

Their tone was that of comrades without a shade of anything deeper.

“Busy?” asked Io.

“Just now.  Give me another five minutes.”

“I’ll go to the hammock.”

One lone alamo tree, an earnest of spring water amongst the dry-sand growth of the cactus, flaunted its bright verdency a few rods back of the station, and in its shade Banneker had swung a hammock for Io.  Hitching her pony and unfastening her hat, the girl stretched herself luxuriously in the folds.  A slow wind, spice-laden with the faint, crisp fragrancies of the desert, swung her to a sweet rhythm.  She closed her eyes happily ... and when she opened them, Banneker was standing over her, smiling.