Abstract
Time was when it seemed every myrmecologist wanted to work on Veromessor pergandei, but we can find no mention of it in the last eight years of Zoological Record. When we lived with it in Death Valley and southern Nevada it became one of our favorite ants.To differentiate instars we would like the following specimens: a first instar inside an egg; a second instar inside a first instar that is ready to moult; a third instar inside a second ready to moult; etc; a mature larva; a prepupa. Fortunately our V. pergandei material meets all the requirements, except the first. V. pergandei is polymorphic, which presents another problem: when does subcaste differentiation begin? How can one tell whether a small larva is the young of a major or a mature of a minim; or whether a mediumsized larva is the mature of an intermediate worker or the halfgrown larva of a major? In V. pergandei subcaste differences apparently begin in the fourth instar and are manifested only in size.V. pergandei presents another problem: there are two body shapes for mature worker larvae. We have no explanation for this.