You have to keep a strong hold on your Freud-dar while reading this "absolutely true book" about Hemingway's late-1933/early 1934 African safari trek in Kenya with his then-wife Pauline Pfeiffer (called "P.O.M.", standing for "Poor Old Mama" in the book), his friend Charles Thompson (called "Karl" in the book) and hunter/guide Philip Percival (called "Pop", "Jackson Phillips", "Mr. J.", "Mr. J.P." "Colonel" etc. at various times in the book).
Hemingway spends the safari mostly unsuccessfully stalking lions, rhinos and kudu (a type of antelope) and even when he returns to camp with occasional trophy horn(s) to show them to "Mama" and "Pop", he also discovers that (surrogate brother) "Karl" has brought back something bigger, longer or thicker. You really do have to keep yourself in check and not let the imagination run too wild while reading this.
Meanwhile you do get very evocative pictures of the African landscape and EH's dealings with his various native trackers and bearers. Two called "M'Cola" and the "Old Man" he becomes especially close to. Another, nicknamed "Garrick", who over-dramatizes events, EH resents more and more and he becomes the only villain (minor really) of the piece for dramatic purposes. EH provides occasional commentary on his writing influences and also uses the opportunity to take an anonymous swipe at Gertrude Stein for her labelling him a coward in her then (1933) recently published "The Autobiography of Alice B. Toklas".
This is a feast for Hemingway lovers, but you should read between the lines to get the most out of it. It is also useful background to reading the short stories "The Snows of Kilimanjaro" and "The Short Happy Life of Francis Macomber" which were also inspired by this same safari.