A number of enigmatic manuscripts of Plato have been identified during the last few decades. Thus Mercati (Studi e Testi 164(1952), 35) showed that Angelicus c.1.9 (w), which L. A. Post (The Vatican Plato and its Relations, pp. 73 f.) was unable to trace, is identical to Rossianus 17(558); N. G. Wilson (Scriptorium 16(1962), 393 n.2) proved that the long-lost Hassistenianus is no other than the Lobcovicianus in Prague University Library (this had already been suspected by H. Alline, Histoire du texte de Platon, p.237, n.3) Here is the solution of a thirdpuzzle.