PERFECT SOCIETIES OF INSECTS. 43 



the ground, hung over the army marching below, and 

 by striking their forceps upon the leaf, produced at in- 

 tervals the noise before mentioned. To this signal the 

 whole army returned a hiss, and obeyed it by increasing 

 their pace. The soldiers at these signal-stations sat 

 quite still during the intervals of silence, except now and 

 then making a slight turn of the head, and seemed as 

 solicitous to keep their posts as regular sentinels. The 

 two columns of this army united after continuing sepa- 

 rate for twelve or fifteen paces, having in no part been 

 above three yards asunder, and then descended into the 

 earth by two or three holes. Mr. Smeathman continued 

 watching them for above an hour, during which time 

 their numbers appeared neither to increase nor dimi- 

 nish : the soldiers, however, who quitted the line of 

 march and acted as sentinels, became much more nume- 

 rous before he quitted the spot. The larvae and neuters 

 of this species are furnished with eyes. 



The societies of Termes luctfugtis, discovered by La- 

 treille at Bourdeaux, are very numerous ; but instead of 

 erecting artificial nests, they make their lodgement in 

 the trunks of pines and oaks, where the branches diverge 

 from the tree. They eat the wood the nearest the bark, 

 or the alburnum, without attacking the interior, and 

 bore a vast number of holes and irregular galleries. 

 That part of the wood appears moist, and is covered 

 with little gelatinous particles, not unlike gum-arabic. 

 These insects seem to be furnished with an acid of a 

 very penetrating odour, which perhaps is useful to them 

 for softening the wood 3 . The soldiers in these societies 

 are as about one to twenty-five of the labourers 5 . The 

 a Latr. Hist. Nat, xiii. 64. b N. Did. If Hist. Nat. xxii, 57, 58. 



