Case Endings and Gender

Greek Learning Greek
1

In Mounce’s Basics of Biblical Greek 4th ed. he stated on page 36 that "words ending in οσ (dont know how to type sigma final) are usually masculine, words ending in ον are always neuter and words ending in α or η are mostly feminine.

Then on page 41 when he covers his case endings chart he says “The masculine and feminine case endings are often similar or even identical”.

I am confused, which is it?

The case ending chart (has nom sg, gen sg, dat sg, acc sg, etc…) also resembles nothing of this first statement about gender ending as the endings in the case charge look evenly distributed.

Can anyone help me reconcile these two statements that to me appear to be contradictions (I am sure I am missing something).

Thank you.

2

The first statement refers to the dictionary form of the nouns (the nominative singular).
The second statement is, I guess, Mounce’s way to make you notice that Masc./Fem. nouns often share endings, with Neuter being the outlier:
Nominative plural: -o_i_/-a**i** vs. -a
Accusative plural: -ou**s/-as** vs. -a