86 



THE AMEEICAN ENTOMOLOGIST. 



juices of the body and causing an intolerable 

 itcliing-, until tliey reach maturity, when they 

 come forth out of their burrows to copulate and 

 lay eggs for tlio future propagation of their 

 species. 



The favorite liome of the Head-louse, as be- 

 fore stated, is the head ; that of the Body-louse 

 tlic more naked parts of the body; the Crab- 

 louse, on the otlier hand, peculiarly affects the 

 human pubes, thougli it occasionally strays off 

 into the whiskers and the eyebrows.* 



All the above tlirop insects, as well as their 

 eggs, may be readily killi'd by the apijlication to 

 the infested portions of the l)<id.\- of a small 

 quantity of any kind of mercurial ointment — 

 whether white, red or black is immaterial, 

 though the white is preferable on account of its 

 not soiling the linen. In the case of the Body- 

 louse, however, as already stated, a frequent 

 change of linen is all that is required to rid one's 

 self of the enemy; and, moreover, the applica- 

 tion of any mercurial ointment to the whole 

 surliice of the body, inhabited by this insect, 

 would be injurious to delicate constitutions. 



The Human Bot-Fly {CEstrushominis, Gme- 

 lin). — Most persons are aware that there is a 

 two-winged fly (CEstrus bovis, Linn.), the larvffi 

 (ifwliich, both in Europe and America, hatch 

 out from eggs deposited by the mother-fly in the 

 hide of the living ox, and cause therein ulcers 

 which are popularly known as "Wormals" 

 (worm holes). There is another species of the 

 same family (C'literebra cunicnli, Clark), the 

 larviB of Avhicli inhabit similar ulcers in the 

 neck of American rabbits ; and still another 

 ( Cuterebra emasculator, Fitch) , wMch in tlie lar- 



raiiged the ' 

 orcU'i- (Hefc 

 ilv of the or 



If buga 



lid not aiiio be placed iu a seijarate 

 'o-ncuroptera should be annexed to 

 le Neuroptera is another and a very 



va state mutilates the generative organs of 

 American squirrels, so as to cause that very 

 general emasculation of these animals, which 

 has been erroneously attributed, by many, to 

 battles between the old and the young males. 



In several parts of South America a larva be- 

 longing to this same family of insects, inhabits 

 " wormals" in the human body, tlie parent fly 

 liaving every facility for depositing its eggs in 

 the naked bodies of the natives, and being 

 enabled to attack civilized foreigners whenever 

 they .strip to bathe. Since, however, this fly ia 

 not found in North America it will not be ne- 

 cessary to say anything further about it.* 



The Comsiox Flea {Pulex irritans, Linn.) — 

 Most of us are so well acquainted with this in- 

 sect in its perfect state, that it is not worth while 

 to dwell upon its peculiarities. It is not, how- 

 ever, so generally known that its larva is an 

 elongate, wriggling worm, totally unlike the 

 mother insect, and that it feeds upon particles 

 of clotted blood deposited along with the egg 

 upon the floor of apartments by the mother flea. 

 Hence fleas cannot multiply in a room where the 

 floor is continually scoured and swept; and 

 hence, also, we may deduce the practically im- 

 portant corollary, that the modern practice of 

 laying down a permanent carpet iu bed-rooms, 

 instead of the old-fashioned bedside carpets, 

 which used to be taken up every few days and 

 shaken in the open air, atfords decided facilities 

 for the propagation of the flea. 



Entomologists differ as to whether the fleas 

 ought to be placed in a small order by them- 

 selves (ApJianiptei-a) , or whether they should 

 form an abnormal family of the order of two- 

 winged flics (Dipicra). As they agree in almost 

 every respect with the two-winged flies, except 

 in having but the merest rudiments of wings, 

 the latter seems the preferable course. After all, 

 these questions are questions rather of words than 

 of things, and of taste rather than of science. 



It is commonly supposed that the flea that in- 

 fests the dog is the same species as that which 

 infests man ; and that, consequently, dog-fleas 

 can exist, flourish, and multiply in bed-chambers 

 where there arc no dogs. All entomologists, 

 liowever, are agreed that each species of flea is 

 peculiar to a distinct species, or at all events to 

 a disliiict genus, of animals; and we have de- 

 sirijiiioiisdf some ten distinct fleas, inhabiting 

 respectively man, the dog, the cat, the squirrel, 

 the hedgehog, the mole, the mouse, the bat, the 

 Australian porcupine {Echidna), and the do- 

 mestic fowl. We have ourselves found a small 

 species upon the young of the common raccoon. 

 • See on this curious subject Say's works, II. , pages 32-38 



