The mathematical diary of Gauss (1777-1855) ended on 7 July 1814 with a remarkable expectation about modulo p solutions of a relation between lemniscate functions. His view and intuition in this "Last Entry" are precise. We see that his idea preludes developments only started more than a century later.

- We explain the statement by Gauss, and

- we show how his idea connects with the "Riemann Hypothesis in positive characteristic" as developed after 1921,

- and we give a proof of this expectation.

- We will sketch several interesting lines in the development of mathematics.

Concepts and ideas involved will be clear to a broad audience of mathematicians. For everyone with just some background in algebra this is understandable and interesting material.