First Edition. Paul Bransom dustjacket art and illustrations. Rare Bleiler listed 'Lost Race' fantasy novel in which two boys return to the hidden land of the Incas and encounter a ruthless king and Sabertooth tigers. Extremely uncommon in original publisher's illustrated dustjacket printed on thin paper stock. Near Fine in Good dustjacket with some internal chipping to spine, splitting along spine edges and at mid-spine mended at verso with archival tape, chipping along rear flap edge, some shallow edge chips.