“At last,” asked Dick Sand, “will you tell us, Mr. Benedict, what is this fly?”

“This fly,” replied the entomologist, “this fly that I hold between my fingers, this fly—­it is a tsetse!  It is that famous dipter that is the honor of a country, and, till now, no one has ever found a tsetse in America!”

Dick Sand did not dare to ask Cousin Benedict in what part of the world this redoubtable tsetse was only to be met.  And when his companions, after this incident, had returned to their interrupted sleep, Dick Sand, in spite of the fatigue which overwhelmed him, did not close his eyes the whole night.

* * * * *

CHAPTER XVIII.

THE TERRIBLE WORD.

It was time to arrive.  Extreme lassitude made it impossible for Mrs. Weldon to continue any longer a journey made under such painful conditions.  Her little boy, crimson during the fits of fever, very pale during the intermissions, was pitiable to see.  His mother extremely anxious, had not been willing to leave Jack even in the care of the good Nan.  She held him, half-lying, in her arms.

Yes, it was time to arrive.  But, to trust to the American, on the very evening of this day which was breaking—­the evening of the 18th of April, the little troop should finally reach the shelter of the “hacienda” of San Felice.

Twelve days’ journey for a woman, twelve nights passed in the open air; it was enough to overwhelm Mrs. Weldon, energetic as she was.  But, for a child, it was worse, and the sight of little Jack sick, and without the most ordinary cares, had sufficed to crush her.

Dick Sand, Nan, Tom, and his companions had supported the fatigues of the journey better.

Their provisions, although they were commencing to get exhausted, had not become injured, and their condition was satisfactory.

As for Harris, he seemed made for the difficulties of these long journeys across the forests, and it did not appear that fatigue could affect him.  Only, in proportion as he neared the farm, Dick Sand observed that he was more preoccupied and less frank in behavior than before.  The contrary would have been more natural.  This was, at least, the opinion of the young novice, who had now become more than suspicious of the American.  And meanwhile, what interest could Harris have in deceiving them?  Dick Sand could not have explained it, but he watched their guide more closely.

The American probably felt himself suspected by Dick Sand, and, no doubt, it was this mistrust which made him still more taciturn with “his young friend.”

The march had been resumed.

In the forest, less thick, the trees were scattered in groups, and no longer formed impenetrable masses.  Was it, then, the true pampas of which Harris had spoken?

During the first hours of the day, no accident happened to aggravate the anxieties that Dick Sand felt.  Only two facts were observed by him.  Perhaps they were not very important, but in these actual junctures, no detail could be neglected.