174 INDIRECT INJURIES CAUSED BY INSECTS. 



mologist is a mite (^Acarus destructor Schrank) : this, if his specimens be 

 at all damp, eats up all the muscular parts i^Cantharis vesicatoria being 

 almost the only insect that is not to its taste), and thus entirely destroys 

 them. If spiders by any means get amongst them, they will do no little 

 miscliief. — Some I have observed to be devoured by a minute moth, per- 

 haps Tinea insectella} ; and in the posterior tliighs of a species o{ Locusta 

 from China I once found, one in each thigh, a small beetle congenerous 

 with Antherophagus pallens, that had devoured the interior. It is, I 

 believe, either Acarus destructor or Cheyletus eruditus that eats the gum 

 employed to fasten down dried plants. 



There are other insects which do not confine themselves to one or two 

 articles, but make a general and indiscriminate attack upon our dead stock. 

 Ulloa mentions one peculiar to Carthagena, called there the comegen. 

 which he describes as a kind of moth or maggot so minute as to be scarcely 

 visible to the naked eye.^ This destroys, says he, the furniture of houses, 

 particularly all kinds of hangings, whether of cloth, linen or silk, gold or 

 silver stuffs, or lace; in short, every thing except solid metal. It will in 

 a single night ruin all the goods of a warehouse in which it has got footing, 

 reducing bales of merchandize to dust without altering their appearance, 

 so that the mischief is not perceived till they come to be handled."^ If 

 we make some deduction from this account for exaggeration, still the amount 

 of damage will be very considerable. 



There are three kinds of insects better known, to whose ravages, as 

 most prominent and celebrated, I shall last call your attention. The 

 insects I mean are the cock-roach (^Blatta orieiitalis), the house-cricket 

 (Gryllus domesticus), and the various species of white ants (^Termes). 

 The last of these, most fortunately for us, are not yet naturalized. 



The cock-roaches hate the light, at least the kind that is most abundant 

 in Britain (for B. gcrmanica, which abounds in some houses, is bolder, 

 making its appearance in the day, and running up the walls and over the 

 tables, to the great annoyance of the inhabitants), and never come forth 

 from their hiding-places till the lights are removed or extinguished. In 

 the London houses, especially on the ground-floor, they are most abundant, 

 and consume every thing they can find, flour, bread, meat, clothes, and 

 even shoes."* As soon as light, natural or artificial, reappears, they all 

 scamper off as fast as they can, and vanish in an instant. These pests 

 are not indigenous here, and perhaps no where in Europe, but are one of 

 the evils which commerce has imported ; and we may think ourselves 

 well off that others of the larger species of the genus have not been 

 introduced in the same way — as, for instance, Blatta gigautea, a native 

 of Asia, Africa, and America, many times the size of the common one, 

 which, not content with devouring meat, clothes, and books, even attacks 

 persons in their sleep, and the extremities of the dead and dying.^ 



The house-cricket may perhaps be deemed a still more annoying insect 



' Atropos puhatorious does much mischief by devouring the more delicate parts of minute 

 insects in collections in which camphor or some other insectiiuge is not kept. 



* It appears from Humboldt {Personal Narrative, E. T. v. 116.) that the destructive 

 insects called by this name are Termites. 



3 Ulloa, i. 67. * Aman. Acad. iii. 345. 



* Drury's Insects, iii. Preface. 



