Chapter XXI: Section IV: PART V.--INSECTA (Coleoptera, Diptera, Hemiptera,

Aphaniptera).

Whilst very many flies, bugs, lice, and fleas persecute animals, not a few of them also attack man. Several of the species are genuine parasites, others are semi-parasitic, and others, again, are altogether outside the border-land of parasitism in the ordinary sense of the term. In fact, it becomes difficult to say where the line of parasitism should be drawn. I cannot, however, ignore all notice of the insect tormentors, whether strictly parasitic or not.

At least fifty different species have been regarded as playing the rôle of parasitism in man. Amongst the Coleopterous parasites none is more authentic than _Blaps mortisaga_. At least half a dozen such cases have occurred. Mr Hope’s catalogue of insects producing parasitism in man gives three examples of _scolechiasis_ from this source. Sir J. R. Cormack published a fourth case, and I have recorded a fifth. In this instance I received the living larva from Dr Horne, of Barnsley, who procured it from an infant eleven weeks old. In my ‘Introductory Treatise’ I have alluded to the case of the girl Riordan, who not only passed per anum upwards of 1200 larvæ, but also several perfect insects. The case was first reported by Pickells, Thomson, and Bellingham. One of the other authentic cases, in which only a few larvæ were present, was recorded by Patterson, of Belfast, and the third case by Bateman. Mr Hope’s ‘Catalogue’ originally appeared in the ‘Transactions of the Entomological Society,’ being afterwards published in the pages of the ‘London Medical Gazette,’ 1837. Patterson’s case was also, I believe, first communicated to the Entomological Society.

As regards the mode in which the maggot gained access to the child in Horne’s case, it was not easy to decide; but in the case of the girl Riordan the mode of ingress was sufficiently explained. The _Blapsidæ_, as a family, are closely allied to the meal-worms, and, like most of the _Tenebrionidæ_, are black and foul-smelling beetles, frequenting dark and damp situations, from which they escape only at night. The family comprises numerous species, of which probably not more than three are found in this country. They are abundant in Africa, especially in Egypt, where (according to Fabricius, as quoted by Westwood, Figuer, and others) the women eat _Blaps sulcata_ cooked with butter in order to make themselves grow fat. The insects are also employed as specifics against ear-ache and the bite of the scorpion. The superstitious notion of a “charm” is generally at the bottom of these domestic remedies. In the girl Riordan’s case, as Westwood observes (when epitomising Pickell’s account), the parasites, as such, “probably originated in an absurd and superstitious practice, which she had for some time followed, of drinking daily for a certain time a quantity of water mixed with clay, taken from the graves of two Catholic priests, and eating large pieces of chalk. One of these beetles was immersed repeatedly in spirits of wine, but revived after remaining therein all night, and afterwards lived three years.” The intolerance of light shown by the perfect insect seems to be equally shared by the larva. Of this fact I had repeated evidence by observing the behaviour of the living specimen sent to me by Dr Horne. Thus, when, on February 5th, 1877, I placed the maggot on the surface of some moist mould, scarcely half a minute elapsed before it commenced to bore its way downwards, and in less than a minute all but the tip of the tail had disappeared. In like manner, when, on the 7th, I raised the lid of the box, and found the maggot on the surface of the soil, it almost instantly proceeded to bury itself. Hope’s list records no less than nine instances of parasitism in man from the larvæ of _Tenebrio molitor_, and he gives a score of other Coleopterous insects which he regarded as human “intestinal worms.” Undoubtedly a large number of insect larvæ do get introduced into, and actually live within the human intestines.

Numerous cases of this sort have come under my observation, but it often requires a profound knowledge of entomology to determine the species. Several examples of œstridean larvæ occur amongst them. For one example of _Œstrus hominis_ I am indebted to Mr Higginson, of Liverpool, who obligingly supplied me with notes of the case. Dr Kirk presented me with a small bot which he removed from Livingstone’s leg. I afterwards deposited the African bot, in his name, in the Hunterian collection. Bates speaks of an Œstrus in Brazil producing boils in human flesh. Westwood quotes similar instances. Of these, one was extracted from the thigh by Dr Brick. Mr Doubleday, the entomologist, extracted one from his own leg, and M. Goudot, another entomologist, was also victimised in the same way. Both of these _savans_ were travelling in America at the time. Two cases from South America were also recorded by Howship. In one the larva lodged in the back; in the other in the scrotum. Humboldt noticed that the Indians were much infested by Œstridæ. Three cases are severally recorded by Roulin, Guérin, and Audouin. Mr Stroop also mentions a case in which an Œstrus was removed from an ulcer on the shoulder of a boy in Texas. Another kind of bot known as the Macaco worm (_Cuterebra noxialis_) occasionally attacks man, but more frequently cattle and dogs. For one example, taken from the leg of a negro, at Belize, British Honduras, I am indebted to Dr Dobson (A. M. D., Netley). Hope’s list records five cases of bots of _Œstrus hominus_, one of _Œ. Guildingii_, one of _Œ. bovis_, and thirteen others (belonging to the same genus) as having been noticed in man. Since his time many additional cases have been recorded by J. M. Duncan and others. In like manner a legion of cases in which the maggots of various Muscidæ have been noticed, either in, upon, or from the human body. At a meeting of the American Academy in April, 1859, Dr Leidy showed some larvæ of the bluebottle fly vomited by a child; five larvæ of the flower-fly (Anthomyia) from a physician’s own person (which had produced choleraic symptoms); and nine examples of _Cuterebra noxialis_. I have myself encountered numerous insect larvæ in medical practice. Amongst others I have obtained the larvæ of _Anthomyia canalicularis_ in six or eight separate instances. One set of specimens, identified by Wunderlich, was sent to me by Dr Brandt, of Oporto. Drs Duffin, W. Fox, and Leared have supplied me with others. The larvæ described in Farre’s case, not being setose, must be referred to one or other of the Muscidæ proper. Mr Hope gave nearly forty cases of this kind, referable to eight different species of fly, and, as already implied, I have myself collected a great variety of the maggots of Muscidæ passed by the bowel, besides others obtained either from beneath the skin or from open ulcerations.

The flies hitherto noticed as supplying parasitic maggots in man are _Musca domestica_, _M. carnaria_, _M. larvarum_, _M. nigra_, and perhaps _M. Cibaria_, _M. stabulans_, and _M. Cæsar_. This last, a handsome fly, is the species which proves so troublesome to sheep. The habit which flies have of depositing their eggs in open wounds, when the victims are asleep, is a fertile source of this kind of parasitism. Some of the instances recorded by Kirby and Spence are revolting in the extreme. They quote the cases which came under Mr Sell’s notice in Jamaica. In one instance the flies were hatched in a neglected blister on the chest; in another from the gums and inside of the cheek; and in a third, from the nostrils of a negro, from whom 235 larvæ were expelled. The case of the Lincolnshire pauper, Page, who was literally eaten up by maggots, is almost incredible. An equally horrible instance, however, is recorded by Cloquet. It is said that the Jamaica cases were all due to the larvæ of the bluebottle fly (_M. vomitoria_). An instance of the same kind has been recorded by Mr Knox (A. M. D.). Sufficiently revolting as these cases are, the horrors attending them are eclipsed by the habits of the larvæ of _Lucilia hominivora_. The best accounts of its habits are those by M. Coquerel, M. Saint-Pair, and M. Vercammer. The insects lay their eggs in the mouth and nostrils, and when the larvæ escape they devour the tissues surrounding the buccal cavity, the pharynx, glottis, frontal and nasal sinuses, even reaching the sockets of the eye. Several Cayenne convicts have perished from the maggots of this fly, which is also prevalent in Mexico. These are not, however, the only instances of maggots gaining access to the nasal chambers. In a case recorded by Dr Astros, of Aix, 113 were discharged from the nose of a woman; and M. Legrand du Saulle records an instance where a number of larvæ occupied the frontal sinuses of a girl, nine years of age. The larvæ produced persistent headache and convulsions. In the case recorded by Wohlfart, 18 larvæ were discharged from the nose of an old man, and in the example given by Latham several larvæ were obtained from the frontal sinuses of a woman. Bracey Clark also gives an instance in which a bot was taken from a woman’s jaw. Not improbably the well-known Indian disease, termed peenash, or worm in the nose, is due to the presence of Œstridean larvæ. Cases by Rustomjee and Lahory are quoted below. Possibly Stockett’s is another of the same order. The case by Kilgour (Bibliog. No. 34) may be another. I may add that Moquin-Tandon gives an instance of the discharge of seventy-two bots, resembling those of the sheep, from a woman’s nose (‘Journ. de Vandermonde’). The rat-tail maggots or larvæ of _Helophilus_ are parasitic. Two or three instances have been recorded from the horse. I possess one from the human intestine. Kirby also quotes an instance in which _Heloph. pendulus_ was obtained from the stomach of a woman (‘Philos. Mag.,’ vol. ix, p. 366).

A vast number of non-parasitic insects are injurious to man and beast. Inasmuch as they subsist at the expense of their victims and also adhere to his person during their attacks for a shorter or longer time, they, like the leeches, may be spoken of as free parasites. The leg-sticker (_Stomoxys calcitrans_) penetrates through thick stockings, causing blood to flow freely. The clegg of the West Highlands (_Hæmatopota pluvialis_) also violently attacks man and beast, especially horses. The mosquito (_Culex anxifer_), the gnats (_C. pipiens_, _C. annulatus_, and _C. pulicaris_), and the midge (_Chironomus plumosus_) need only be mentioned. The creeping gnat (_Simulium reptans_) is also very annoying in Sweden. The rôle of the mosquito, as itself constituting a parasite-bearer, will be again referred to in the closing pages of this work (Book II, Section V). The bites of the tsetse (_Glossina morsitans_), though so destructive to the horse, ox, sheep, and dog, are not dangerous to man himself. According to Sir S. Baker, the seroot-fly, or zimb of Bruce, which is a species of _Pangonia_, is excessively annoying to travellers in Abyssinia. Amongst the hemipterous insects the common bug (_Acanthia lectularia_) is sufficiently blood-thirsty; but there is a far more sanguinary species of this kind in South America. This is the pampas benchucha (_Conorhinus nigrovarius_). Our distinguished countryman, Darwin, in his ‘Voyage,’ speaking of these wingless insects, says:--“Before sucking they are quite thin, but afterwards become round and bloated with blood. In less than ten minutes the insect is changed from being as flat as a wafer to a globular form.” This insect somewhat resembles our water-scorpion (_Nepa cinerea_), a non-parasitic species whose bite causes severe pain, as does also the wound inflicted by the water-boatman (_Notonecta glauca_). There are other species of bug, such as the _Acanthia rotundata_ of Réunion Island and _A. ciliata_ of Kasan, the bites of which are worse than that of the common species. The fly-bugs also, such as the _Reduvius personatus_, so common in France, and the _R. amænus_ of Borneo and Java, attack man, although their especial habit is to attack and destroy other insects, including bugs themselves. Other species or varieties of Reduvius (_R. cruentus_, and _R. serratus_) attack man. The last named is an Indian form, capable, it is said, of producing an electric shock.

Passing to the fleas, the most important and truly parasitic form is the chigoe or gigger (_Pulex penetrans_). This abounds in tropical America and the West Indies. The female insects only attack man, and this they do for the purpose of securing a lodgment for their offspring. They attack especially the soles of the feet, between the toes and near the nails. In bad cases the whole of the foot becomes affected. After the insect has penetrated the skin its body swells enormously and becomes a mere bag of eggs. This swelling causes active inflammation, which terminates in suppuration and the formation of open ulcers. The chigoe also attacks various animals. In addition to the common flea (_P. irritans_) other species infesting animals are said to attack man occasionally. As regards those degraded types of insects known as lice I can only afford space to remark that five species have been recognised as human. These are the head-louse (_Pediculus capitis_); the louse of the eyelids (_P. palpebrarum_); the clothes-louse (_P. vestimenti_); the distemper louse (_P. tabescentium_); and the pubic louse (_P. inguinalis_). The distress these creatures occasion is only fully known to physicians who deal with the obstinate cutaneous affections caused by their presence (_Phthiriasis_). Some of the lice found on negroes and Greenlanders are regarded as distinct varieties. Lice are abundant on animals, and some of the species are apt to transfer themselves from one host to another. Thus the _Ornithomyia avicularis_ of cage birds has been found on man, whilst one or more of the numerous species infesting the common fowl are, by transfer, apt to produce a severe phthiriasis in the horse. The lice of the fowl belong to the genera _Leipurus_, _Liotheum_, _Menopon_, _Philopterus_, _Goniodes_, and _Goniocotes_. The unsuitableness of man’s person as a habitation for bird-lice should, however, check the fear which many persons have of handling fresh-killed poultry and game birds. Poultry lousiness in man is probably impossible from this source.

BIBLIOGRAPHY (No. 40).--_Arture_, “Obs. sur le ver nommé Macaque,” in ‘Mém. Acad. des Sci.,’ Paris, 1753.--_Bates_, “Œstrus in Man,” ‘The Naturalist on the Amazons.’--_Beneden, Van_, ‘Animal Parasites and Messmates,’ 1876.--_Idem_ (with _Gervais_), ‘Traité de Zool. Méd.’--_Blood, M._, “Case of Larvæ (_Musca sarcophaga_) expelled alive in the Fæces,” ‘Beale’s Arch. of Med.,’ vol. iii, p. 134, 1862.--_Brinton_ (similar case), ‘Arch. of Med.,’ vol. iii, p. 133, 1862.--_Bouyer_ (quoted by Figuer), ‘Tour du Monde,’ p. 318, 1866.--_Clark, Bracey_, in ‘Linn. Trans.,’ vol. iii, 1797 (the jaw-case at p. 323), and vol. xv, 1827.--_Idem_, ‘Essay on Bots,’ 1815.--_Cloquet, J._, “Case of Blindness from Worms (larvæ of Musca) in the Eyes,” from ‘Arch. Gén. de Méd.,’ in ‘Lancet,’ 1828.--_Cobbold_, “On _Blaps mortisaga_ as a Human Parasite,” ‘Brit. Med. Journ.,’ 1877, p. 420.--_Idem_, “Entoz.” (‘Hope’s List.’), p. 416.--_Idem_, in ‘Worms’ (“Leptus,” &c.), p. 140, 1872.--_Coquerel_ (quoted by Figuer).--_Cormack, J. R._, “Exhibition of a Larva (_B. mortisaga_) passed by a Child,” ‘Month. Journ. Med. Sci.,’ vol. i, 1841.--_Crumpe, S._, “History of a Case in which Worms (larvæ of a beetle) were discharged from the Stomach,” from ‘Trans. of the Roy. Irish Acad.,’ vol. vi, in ‘Med. Facts and Observ.,’ vol. viii, p. 229, 1800.--_Denny_, ‘Monog. Anoplurorum Brittaniæ,’ 1842.--_Duncan, J. M._, “On the Occurrence of Bots in the Human Subject,” ‘Edin. Vet. Rev.,’ vol. i, p. 275, 1858-59.--_Idem_, “The Larva of _Œstrus bovis_ in the Human Subject,” ‘Rep. of Edin. Med.-Chir. Soc.,’ in ‘Month. Journ. of Med. Sci.,’ July, 1854.--_Farre, A._, “On the Larva of _Anthomyia canalicularis_,” ‘Micr. Journ. and Struct. Rec.,’ 1841, p. 129, and in ‘Trans. of Micr. Soc. of Lond.,’ orig. ser., p. 51, 1844.--_Figuer_, in ‘The Insect World’ (good figs.), Janson’s edit., 1869.--_Furlonge_, “Anat. of Pulex,” in the ‘Journ. of the Queckett Club,’ vol. iii.--_Geer, De_, ‘Mémoires pour servir à l’Histoire des Insectes,’ 1773.--_Gervais_ (see Van Beneden).--_Hill_, “Account of the Larva of a supposed _Œstrus hominis_, or Gad-fly, which deposits its Eggs in the bodies of the human species, with particulars of a Case,” ‘Edin. New. Phil. Journ.,’ vol. xxii, p. 284, 1830.--_Hilaire_ (see St Hilaire).--_Hope_, “Tables of Cases of (spurious) Intestinal Worms,” ‘Lond. Med. Gaz.,’ 1837-38.--_Hoppe_, “Case of Larvæ of Insects (_Musca stabulans_) passed by Stool,” from ‘Bibl. für Läger,’ in ‘Med.-Chir. Rev.,’ 1842.--_Hopper, R. S._, “Insects (Stratiomis) voided with Urine,” edit. note in ‘Micr. Journ. and Struct. Rev.,’ p. 160, 1841.--_Joly_, ‘Recherches sur les Œstrides en général,’ &c., Lyons, 1846.--_Keferstein_, ‘Sur l’Oistros,’ Isis, 1827.--_Kirby_ (and _Spence_), ‘Introd. to Entomology,’ 7th edit., 1856.--_Knox, M._, “Maggots, the larvæ of the Bluebottle Fly, in Syphilitic Ulceration of the Throat,” ‘Lancet,’ Oct. 6, 1877, p. 514.--_Lahory, B. T. C._, “On _Peenash_, or Worms in the Nose,” ‘Ind. Ann. of Med. Sci.,’ 1855, and ‘Edin. Med. Journ.,’ 1857.--_Leach_, “Œstridæ,” in ‘Wernerian Trans.,’ 1817.--_Leidy_, in ‘Proc. Phil. Acad. Nat. Sci.,’ 1859, p. 7.--_Maclean_, “On the Oistros,” ‘Linn. Trans.,’ vol. xiv, 1824, and in ‘Zool. Journ.,’ vol. i and iv.--_Metaxa_, “Vom Œstrus (u. s. w.),” in ‘Neuen Nord. Beitr.,’ Bd. i, and in ‘Mém. de Zool. Med.,’ Rome, 1835 (quoted by Westwood).--_Moquin-Tandon_, ‘Med. Zool.’ (l. c., Bibl. No. 38).--_Newport_, art. “Insecta,” ‘Todd’s Cyclop.,’ 1839.--_Rustomjee, B._, “Case of Worms in the Nose, or ‘Peenash,’” in ‘App. to Bomb. Med. and Phys. Soc. Trans.,’ No. vii, new ser., p. 21, 1861; see also Lahory, on ‘Peenash.’--_Saint-Hilaire_, “Sur l’Œstre chez l’homme,” in ‘Ann. Soc. Ent. de France,’ 1833.--_Say_, “Brick’s Case,” in ‘Trans. Acad. Nat. Sci. Phil.,’ vol. ii.--_Sells_, in ‘Trans. Entom. Soc. Lond.;’ see also Lemprière’s ‘Diseases of the Army in Jamaica,’ vol. ii.--_Stockett, T. H._, “An account of a Headache cured by the discharge of a Worm (?) from the Nose,” ‘Med. Com.,’ vol. xix, p. 157, 1794, and in ‘Trans. Coll. of Phys. Phil.,’ vol. i, part i, p. 181, 1793.--_Stroop, St J._, “Œstrus,” in ‘Amer. Naturalist,’ vol. vii, p. 437.--_Tanner_, “On Lice,” in his ‘Pract. of Med.,’ vol. ii, p. 429, 6th edit., 1869.--_Westwood_, in his ‘Classification of Insects,’ vol. ii, 1840.--_Wohlfart_ (quoted by Moquin-Tandon).--_Yule_, “Case of Larvæ of Insects in the Human Stomach,” ‘Edin. Phil. Journ.,’ and ‘Lond. Med. Repos.,’ 1825.