Lockwood suppressed a frown, but said nothing, for, a moment later, a young man came in.  Almost in silence he advanced to Inez and took her hand in a manner that plainly showed his sympathy in her bereavement.

“I have just heard,” he said simply, “and I hastened around to tell you how much I feel your loss.  If there is anything I can do--”

He stopped, and did not finish the sentence.  It was unnecessary.  His eyes finished it for him.

Alfonso de Moche was, I thought, a very handsome fellow, though not of the Spanish type at all.  His forehead was high, with a shock of straight black hair, his skin rather copper-coloured, nose slightly aquiline, chin and mouth firm; in fact, the whole face was refined and intellectual, though tinged with melancholy.

“Thank you,” she murmured, then turned to us.  “I believe you are acquainted with Mr. de Moche, Professor Norton?” she asked.  “You know he is taking post-graduate work at the University.”

“Slightly,” returned Norton, gazing at the young man in a manner that plainly disconcerted him.  “I believe I have met his mother in Peru.”

Senorita Mendoza seemed to colour at the mention of Senora de Moche.  It flashed over me that, in his greeting Alfonso had said nothing of his mother.  I wondered if there might be a reason for it.  Could it be that Senorita Mendoza had some antipathy which did not include the son?  Though we did not seem to be making much progress in this way in solving the mystery, still I felt that before we could go ahead we must know the little group about which it centred.  There seemed to be currents and cross-currents here which we did not understand, but which must be charted if we were to steer a straight course.

“And Professor Kennedy?” she added, turning to us.

“I think I have seen Mr. de Moche about the campus,” said Craig, as I, too, shook hands with him, “although you are not in any of my classes.”

“No, Professor,” concurred the young man, who was, however, considerably older than the average student taking courses like his.

I found it quite enough to watch the faces of those about me just then.  Between Lockwood and de Moche it seemed that there existed a latent hostility.  The two eyed each other with decided disfavour.  As for Norton, he seemed to be alternately watching each of them.

An awkward silence followed, and de Moche seemed to take the cue, for after a few more remarks to Inez he withdrew as gracefully as he could, with a parting interchange of frigid formalities with Lockwood.  It did not take much of a detective to deduce that both of the young men might have agreed on one thing, though that caused the most serious of differences between them—­their estimation of Inez de Mendoza.

Inez, on her part, seemed also to be visibly relieved at his departure, though she had been cordial enough to him.  I wondered what it all meant.