702 THE ANIMAL PARASITES OF MAN 



ARTHROPODA. 



Leptus autumnalis (Grass, Harvest, or Gooseberry Mite 1 ). 



IN the hot season of the year, that is, during the months of July 

 and August, it is noticed that those people who stray amongst 

 syringa bushes or who pick gooseberries or kidney beans are 

 attacked by the Leptus autumnalis. On the uncovered parts of the 

 body there appear numerous red spots and papules, which itch and 

 burn smartly. The itching does not commence diffusely, as in the 

 case of scabies (MacLennars 2 ), but is limited to the particular 

 points where the parasite is situated. There are especial outbreaks 

 of itching in the morning, arising perhaps from the hatching of ova 

 in the host after lying in the warmth of the bed. 3 Leptus fre- 

 quently provokes general erythema, eczematization or severe feverish 

 urticaria, which in France is known by the name of fievre de grain 

 (Megnieu, Besnier 4 ). If the individual efflorescences be carefully 

 examined, there will be noticed almost without exception a minute 

 boss towards the centre, noticeable by its yellowish-red colour. If 

 an attempt is made to remove it with the point of a needle or to 

 scrape it off the surface, one can often perceive, even with the naked 

 eye, a small reddish creature moving actively about. The treatment 

 of these very troublesome symptoms consists in warm baths with 

 soapy lavages, also lavages with alcohol, spirit salmiac (G. P.), 5 per 

 cent, carbol or creolin solution, diluted vinegar, benzine, emulsions of 

 balsam of Peru, rubbing in sulphur ointment (Sandwith 5 ) ; ointments 

 of creosote or eucalyptus are recommended. Other grass and grain 

 mites also occasionally penetrate the skin of man and produce transi- 

 tory but sometimes very severe eruptions, urticaria and eczema 

 papulosum, as Geber 6 and subsequent to him Josai 7 have reported 

 of the barley mite. In sensitive individuals the skin becomes bright 

 red, to a greater or less extent their temperature is raised and fre- 

 quently slight febrile affections are present. If the inflammatory 



1 There is no reason for calling this the gooseberry mite. It is rarely found on this 

 fruit. The gooseberry mite is Bryolia pretiosa. 



- MacLennars, Lancet, 1905. 



* [This cannot be the case, as Leptus autumnalis is the larval form of Trombidium holo- 

 sericeum. F. V. T.] 



4 Sack, " Handb. d. Hautkrankh.," v. Mracek, 1907. 



5 Sandwith, Lancet, 1905. 



6 Geber, " Handbuch d. Hautkrankh.," in v. Ziemssen's " Handbuch d. spez. Pathol. 

 u. Therap.," 1884, xiv. 



1 Josai. 



