116 



THE ENTOMOLOGIST S RECORD. 



The habits and instincts were nearly if not quite as advanced then 

 as now. A number of specimens have been found in one block of 

 amber together with plant-lice, showing that these ants had learnt to 

 attend Aphids, and as some myrmecophilous beetles occur in the amber, 

 it is evident that the ants already kept myrmecophiles in their nests. 

 Wheeler figures a worker of Lasiiis nhiefferdeckeri, one of two specimens, 

 each of which is bearing a mite attached to the base of one of the 

 hind tibiae. This not only shows that these ants had Acarine parasites, 

 but also that the latter had already acquired the habit of affixing them- 

 selves to definite parts of their host's body, as is the case with species 

 of Cilibano and Antennophorits to-day. It is also probable that the 

 amber ants had established parasitic relations with one another, as in 

 our present slave-makers and temporary social parasites. 



Wheeler was unable to find any Fonnira species with a clypeus 

 formed like that of our present F. santiuinea, but as his remarkable 

 Pityomyrmex tornquuti (although it belongs to the Dolichodermae) bears 

 a striking resemblance to the' modern " Amazon ant," Polyer;/us 

 riifescens, he considers it is probable it possessed similar habits. 

 Formica phaHhusa Wheeler belongs to the 7^^. rufa group, and as shown 

 by Wheeler in America, Wasmann in Holland and Luxemburg, and 

 the writer in Britain, all the known forms of this group are temporary 

 social parasites on F. fnaca or some of its varieties ; it is therefore 

 exti-emely probable that F. pliaHknsa founded its colonies with the aid 

 of F. fiori colonies. 



In connection with the genus l^'ormica, W' heeler writes: — "With 

 the discovery in the Baltic amber of three new species of bonitica, one 

 allied to the recent cinerea and. two belonging to the rufa group, Was- 

 mann's recent speculations concerning the phylogeny of the genus are 

 deprived of their last slender support and fall to the ground, because it 

 can be no longer asserted that F. liori, which is very closely related to 

 the recent F. fusca, is the oldest and most primitive species, and that 

 F. rufa and F. sauguinea are descended from such a form." 



It is very difficult to fix the time and place of the origin of the 

 Formicidae as a family, as no ants are known from the periods ante- 

 dating the Baltic amber. 



Handlirsch has suggested that as some primitive Hymenoptera 

 occur in the Upper Jura, and ants are found in the Lower Tertiary, the 

 original ancestors of the latter cannot have put in an appearance before 

 the Upper Chalk. As Wheeler, however, points out, very few Mesozoic 

 insects are known, and it is evidently possible that ants may have 

 coexisted with more primitive Hymenoptera during the Jurassic, just 

 as the primitive group of Blattoidea (cockroaches) coexist to-day with 

 highly specialised and very recently evolved insects. 



Wheeler agrees with Handlirsch, that our present knowledge of 

 Formicid distribution does away with the necessity of postulating the 

 existence of great sunken continents, and. is willing to agree that the 

 fainily maj^ have originated in Eurasia. Handlirsch, however, was 

 mistaken in thinking that the North American Tertiarj^ ant-fauna was 

 insignificant. The existence of numerous fossil ants which Wheeler 

 has examined from the Florissant shales, makes it very probable that 

 there must have been ants in North America during the Eocene, and if 

 the migration of the family took place from Eurasia, as Handlirsch 

 supposes, it must have antedated the beginning of the Tertiary at the 

 latest, — Horace Ponisthorpe, 



