Tarzan & the Jewels of Opar / Jungle Tales of Tarzan (Tarzan, #5-6)

Tarzan & the Jewels of Opar / Jungle Tales of Tarzan (Tarzan, #5-6) - Edgar Rice Burroughs Two books for the price of one
Tarzan and the Jewels of Opar
After a business venture collapses, Tarzan decides the best way to get out of this problem is to head off to Opar and steal some of the gold they have left lying around.
A bash on the head leaves him with only the memory of his days growing up with the apes and he reverts to the savage man he once was.
Meanwhile, Jane manages to get herself kidnapped, escape, lost, kidnapped again (and again).

This took a while to get into, with a lot of things having to fall into place before the finale making it a bit of a chore before the action started.

Jungle Tales of Tarzan
Various short stories of Tarzan as a boy growing up with the apes. Some are better than others, but they follow each other logically and lead into the next story quite well.