At this juncture the "caw" of a crow was heard again.

He started slightly, bent his head and listened, but there was no repetition of the signal, for which Crazy Jane McCarthy was devoutly thankful.

It was plain that he knew it was not a crow, that he understood it to be a signal of some sort.
The half-breed suddenly turned, starting toward the shore of the lake at a brisk pace, worming his way through the bushes with almost no disturbance at all, even at the swift pace he was keeping up.
Jane had lost her fear now.

The boys had gone on out of sight and sound and the intruder was hurrying toward the lake.

The girl, however, did not dare to run.