This paper contains two results; the first extends to a wide class of Orlicz spaces the statement, due to Krasnosel'skii and Rutickii [1, p. 60], that L1 is the union of the Orlicz spaces which it contains properly; the second shows that for a wide class of spaces this is not true, i.e. there exists a set of Orlicz spaces no one of which is the union of the Orlicz spaces it contains properly. H-Iere the Orlicz spaces are defined on [0, 1 ] which is given Lebesgue measure ,u. 1. We give in this section several definitions together with some elementary results about Orlicz spaces and convex functions. Let e be the set of convex symmetric functions 4: (oo, co) > [0, oo) suqh that 4(0) = 0, lim8.0 'f(s)/s = 0 and lim,0 4?(s) = co. If 4) and Q are two elements of e, we say 4 < Q if there exist constants c and s0 such that 4P(s)