18 



The question of the position of Myrmecorhynchus among 

 the various tribes and genera of the Camponotinae leads me 

 to a consideration of Forel's most recent arrangement of this 

 subfamily in the sixth part of his "Formicides Neotro- 

 piques." ,4) He divides the Camponotinae into three sections 

 — the Procamponotinae, the Mesocamponotinae, and the 

 Eucamponotinae — on the structure of the proventriculus, or 

 ''gizzard." In the first section, which contains only one genus, 

 the extraordinary Malayan Myrmoteras, the gizzard has a 

 very short calyx, with widely diverging, heavily chitinized 

 sepals, strongly recurved at their tips. The Mesocamponotinae 

 have the calyx reflected and comprise three tribes — the 

 Melophorini (genera Notorious and Melophorus), the 

 Plagiolepidini (genera Rhizomyrma, Plagiolepis, Acantholepis, 

 Acropyga, and the Myrmelachistini (genera Myrmelachista y 

 Aphomomyrmex, Brachymyrmex, and the fossil Rhopalo- 

 myrmexj. The Eucamponotinae, which have the gizzard 

 ''straight or slightly curved, but never reflected," embrace 

 five tribes — the Gesomyrmini (genera Gesomyrmex and 

 Dimorphomyrmex), the Prenolepidini (genus Prenolepi* ), 

 the Formicini (genera Pseudolasius, Lasius, Formica, 

 Polyergus, Myrmecocystus , and Cataglyphis), the Oecophyl- 

 lini (genera Gigantiops, Myrmecorhynchus, and Oecophylla), 

 and the Camponotini (genera Camponotits, Echinopla y 

 Polyrhachis, Dendromyrmex, Calomyrmex, and Opisthopsis). 



While considerable portions of this classification are 

 undoubtedly well founded, there are at least two genera, 

 Myrmoteras and Myrmecorhynchus, whose interpretation and 

 position seems to me to be open to discussion. Forel believes 

 that Myrmoteras is an extremely ancient and primitive type, 

 a veritable "living fossil," which "shows that the Campono- 

 tinae must be directly derived from some primitive aberrant 

 Ponerine like Odontomaclivs, Stigmatomma , or Mystrium ."' 

 He inclines to this view because the worker and female 

 Myrmoteras have a head remarkably like that of Odonto- 

 machus, with long, linear, toothed jaws, inserted close 

 together. It seems to me that he has reached this peculiar 

 conclusion through supposing that an ancient is necessarily 

 a primitive and ancestral form. Undoubtedly Myrmoteras 

 is a very old Mesozoic genus, but its two surviving species, 

 M. binghami, Forel, and M. donistliorpei, Wheeler, are at 

 the same time extremely specialized, as shown by the wing- 

 venation and the structure of the head and legs. The re- 

 semblance to Odontomachus and similar Ponerine genera 

 (which are themselves highly specialized and by no means 

 ancestral forms) are due to convergent development, and 1 



(4) Mem. Soc. Ent,, Belg., 20, 1912, pp. 87 to 92. 





