148 A. C. OUDEMANS. ACARI. 



III. 



HISTORICAL, BIOLOGICAL AND PATHOLOGICAL NOTES 



ABOUT THE NEW GUINEA AND 



OTHER HARVEST-MITES. 



The oldest informations about harvest-mites troublesome to men are those of Throm- 

 bidium batatas (L.). 



In the io th Edition of the Systema Xaturae of LlNNÉ, 1758, we read: 



„Acarus batatas. — A. sanguineus scabriusculus, pedibus anterioribus longitudine cor- 

 poris. Rolander. Habitat in Batatas Surinami." 



The same words are repeated in LlNNÉ, Systema Naturae, Ed. XII, 1767, and in LlNNÉ, 

 Systema Naturae, Ed. XIII, cura GMELINI, 1790. 



I do not know ROLANDER's work. It is not quoted in ENGELMANN's Bibliotheca Zoo- 

 logica. It seems, however, that P. L. S. MOLLER has read ROLANDER, for in his Vollstàn- 

 diges Natursystem nach der XII. lateinischen Ausgabe, Tom. V, Pars II, n°. 25, 1775, he. tells 

 us that the Acarus batatas crawls on the legs of men and causes an itch. 



STOLL in GODMAN and Salvin's Biologia Centrali-Americana, {Arachnoidea and Aca- 

 roidea) does not mention anything about this curious Acarus. 



Recently I found a passage about it in the Tijdschrift van het Koninklïjk Nederlandsch 

 Aardrijkskundig Genootscliap, 1904, Verslag van de Saramacca-Expeditie, p. 22. Hère Mr. 

 Van Stockum tells us: 



„Er komt te Paramaribo een klein venijnig insect voor, dat men hier patatta-luis noemt 

 en waarvan de beten een ondragelijke jeuk veroorzaken. Deze diertjes houden zich voornamelijk 

 tusschen het gras op. Wanneer nu een nieuvveling in de kolonie, dit niet wetende of er niet 

 aan denkende op een grasveld blijft staan, wordt hem door een Surinamer terstond aangeraden 

 op de paden te blijven om niet van deze kleine plaaggeesten op te loopen." 



Though the Zoologist to the Expédition purposely and repeatedly walked on the lawns 

 or grass-fields, he was never attacked, most probably because it was not the right season. 



A second and better known case is that of the larva of Thrombidium holoserïceum (L.), 

 first mentioned by Shaw in his General Zoology, Vol. 6, Part. 2, London 1806, and called 

 by him Acarus autumnalis or Harvest-Mite. It is well known in Great Britain. It crawls upon 

 the legs of the harvesters and causes a troublesome itch. Sometimes also the hands are at- 

 tacked. Also in France it causes a well-known disease, and the literature about the subject 



