Abstract. A description is obtained of all pseudocomplemented semilattices $S$ for which the set of idempotent endomorphisms is closed under composition. Those $S$ for which the endomorphism monoid is orthodox are then identified.
AMS Subject Classification
(1991): 06A12, 20M19; 08A35
Received September 4, 1995. (Registered under 5667/2009.)