Type‐material of 100 insect species described by J. R. Forster has always been thought lost. We present evidence that syntypic specimens of some of these species were sent by Forster to Linnaeus in 1772. Specimens of at least 27 species survive in the Linnaean collection now in Burlington House, and are listed. The identity of each of the 18 species of Hymenoptera described by Forster is examined in detail, particularly the nine represented by specimens. Lectotypes are designated for two species; four new synonymies and two new combinations are established; and three names remainnomina dubiawithin their gener