574 THE ANIMAL PaMSITES Of MAN 



yet been determined with certainty. Some authors, however have thought 

 that they produce another disease, the " creeping disease." 



In the hot summer months it is noticed — the number of cases observed is 

 still limited — that upon the uncovered portions of the body irregular, serpen- 

 tine, linear elevations appear, which never branch, and these give rise to itching 

 and burning, and cause a red elevation, slightly raised above the skin. The 

 line is elongated, and tapers rapidly to a point (1-15 cm. in twenty-four 

 hours). Occasionally at intervals of from 1-3 cm. small nodules are notice- 

 able, which have been declared to be the fecal mass discharged by this insect. 

 That the disease is caused by an animal parasite is certain. The parasite itself, 

 which has been thought to be a gastrophilus larva, has not yet been zoologically 

 and definitely determined. 



The majority of affections of myiosis externa are caused by muscides 

 larvse. In Europe it is particularly the sarcophila Wohlfart, Portschinsky, 

 1875, in America the lucilia macellaria, Pabricius, 1794. Those persons are 

 most endangered who sleep in the open air and who suffer from any purulent 

 process: Pus from the ear, nose, or similar affections. The fly is otherwise 

 extremely timid and never enters living rooms, but is attracted by pus and 

 deposits its eggs. The larvae, which soon come forth, cause remarkable de- 

 struction by their enormous appetite. Entering the auditory passages, they 

 eat the external covering, penetrate the tympanic cavity, and pass through 

 the Eustachian tube into the pharynx. Great destruction is wrought in 

 the nose and its auxiliary cavities, where ulcers and purulent wounds are 

 produced. Autopsy findings confirm the extraordinary virulence of these 

 parasites. 



In the conjunctiva, in the oral cavity, even in the urethra and the bladder, 

 maggots have occasionally been observed. Formerly, before the introduction of 

 antiseptic surgery, maggots in wounds were not very uncommon ; to-day they 

 appear only in such as are grossly neglected. Besides the parasites mentioned 

 above, in man larvae of calliphora vomitoria Eobineau-Desvoidy, cimex limen- 

 sis, sarcophaga carnaria, Meigen, musca cadaverina, musca domestica, musca 

 stabulans, and others have been observed. 



I should like to say here that numerous occasional parasites, such as gal- 

 leria mellonella, dermestes lardarius, geophilus sodalis, geophilus hortensis, 

 thousand-leggers, have been removed by physicians from the nose. Laboulbene 

 mentions a case in which the gammarus pulex was vomited. This by no means 

 exhausts the number of the occasional parasites. 



For their removal, corrosive sublimate injections and chloroform or turpen- 

 tine mixtures are advised. 



The myiosis intestinalis is a much-debated parasite. Although numerous 

 well-observed cases of this kind are on record, the presence of the larvae of flies 

 in the digestive apparatus is still doubted. We shall touch lightly on these 

 doubts which are nowise justified. Those that have been observed up to now 

 are the larva of musca vomitoria, musca domestica, musca nigra, musca cor- 

 vina, musca pendula, musca meteorica, calobata cibaria, hydrothorea meteorica, 

 sarcophaga affinis, sarcophaga carnaria, sarcophaga haemorrhoidalis, sarcoph- 

 aga haematodes, anthomyia canicularis, anthomyia scalaris, etc. 



