186 BRITISH ANTS. 



being always present in the winter, and they take considerably 

 longer to develop than is the case with the larvae of Formica. 



The workers feed the larvae with liquid food, but will also give 

 them bits of dead insects, eggs, and other larvae, etc., to eat. 



The pupae are generally enclosed in cocoons, and both Andre 

 and Saunders state that this is always the case ; but F. Smith, Mayr, 

 Forel, Janet, and I have all recorded instances where a number of 

 naked pupae have occurred. 



These ants are not so warlike, nor so quarrelsome as Formica, 

 and generally act on the defensive, barricading their nests, and the 

 entrances to their subterranean galleries, with grains of earth, 

 when attacked ; but occasionally will pour out in vast multitudes, 

 and overwhelm the foe by sheer weight of numbers. 



Their method of fighting is for five or six workers to seize the 

 legs of their adversary, and hold on. 



Sometimes colonies of different species may be found together, 

 nesting under the same stone, or in close proximity to each other, 

 but it is only in cases where the mixed nest owes its origin to 

 the abnormal method of colony founding that they are really 

 associated. In other cases, where they are living together only by 

 chance, when the nest is disturbed, or the different ants are put 

 into a box, they will at once attack each other. 



The method by which ants of this genus salute each other is very 

 characteristic ; it has already been described by Crawley, and as 

 far as is known to me he is the only myrmecologist who has pub- 

 lished an account of this curious action. 



When two specimens of Donisthorpea meet, one of the ants will 

 be seen to make a succession of rapid jerks of the body towards 

 the other, which lasts for several seconds. This motion does not 

 consist in striking the head against the other ant, and the only parts 

 of the body touching at the time are usually the antennae. On un- 

 covering an artificial nest of D. flava or nigra and exposing it to 

 the light, almost every ant may be seen thus jerking its whole 

 body to its neighbours. An ant may be seen in an artificial nest to 

 salute nearly every ant it meets. The workers greet young winged 

 females and males in the same manner, and the females sometimes 

 respond, but the males never do. I have seen young winged 

 D. umbrata females frequently salute each other in this manner 

 when they met. A young fertile female will respond to the salutes 

 of her first brood, but an old female in a large nest never does so. 



Fabricius [Syst. Piez. 415 (1804)] published a heterotypical genus 

 Lasius for the reception of ten species of ants, but this use of the 

 name is invalid since Lasius (Type Apis quadrimaculata Panz.) had 

 already been used by Jurine for a genus of Bees [Erlangen Litt- 

 Ztg. 1 164 No. 33 (1801) : Nouv. Meth. Hym. 235-238 No. 33 Pf. 

 4-33, 11-33 (1807)]. Latreille [Gen. Crust. Ins. 4 126 (1809)] sunk 

 Lasius F., as a synonym of Formica, and the Fabrician name 



