4.6 THE CAUSES WHICH PEOPAGATE 



Many ants are pregnant with this formic acid of chemists, 

 but some are offensive with a smell of odour, as the Formica 

 fcBians of Fabricius. The hairy Solitary Ants and the Wild 

 Bees {Andreniilcp) have a taint of garlic ; and some of this 

 order that spin moth-like cocoons, as Bembex and Sphex, 

 emit sudden puffs of ether, as do the little wasp-like species of 

 the genus Crabro ; but Cimbex emits a smell of musk. The 

 large yellow European Scolia flavours of certain red aromatic 

 cachous lozenges frequently seen on the counters of apothecaries' 

 shops ; and the gall insects of the oaks have, I believe, a dis- 

 agreeable odour. The secretory glands of the Bugs are situated 

 exterior to the insertion of the posterior legs, and emit foetid 

 effluvia on seizure, smacking of ratafia ; or of that undefinable bug 

 odour that annoys us so much when gathering raspberries ; but 

 many of the flat Plant Bugs take besides a very distinct smack of 

 fruit essences — Capsus tricolor one of black currants, and Hetero- 

 toma is thought to flavour of sliced cucumber ; one of the 

 Pentatomidse smells of the fresh hillside thjme, and the other- 

 wise disgusting scale-like Enojjlops scaj^iha (Fab.) has a faint scent 

 of the autumn ripe peach ; another smells of hyacinth. In the 

 Reduviidse, or Musical Bugs, we And the' ordinary hemipterous 

 odour quite exchanged for that acid vinegary perfume found in 

 so many insects. 



The aquatic species of Corixa possess the bug odours, and 

 the Water Boatmen, that oar on their backs, smack of the large 

 Water Beetles. The odoriferous organ of the Land Bugs, Leon 

 Dufour found to consist in a rather large jDouch, rarely two, 

 situated at the base of the abdomen, just below the digestive 

 viscera, most often of a yellow or orange colour; its raised orifices 

 lay on the thorax between the insertion of the second and third 

 pairs of legs. Seize the common Grey Pentatoma, and plunge it 

 in a glass filled with clear water, he says ; " arm your eye with 

 a lens, and you will see a number of little globules arise which, 

 on breaking at the surface, diffuse the easily-recognisable and 

 noxious odour of the bugs. This vapour, essentially acid, will 

 both irritate the eyes, and leave a brown mark on the skin 

 similar to that of a mineral acid." 



Certain Cicadte, according to Mr. Bates, unite the three 

 stimuli of music, colour, and secretion, and the last is em- 



