20 (de. a. C. OUDEMANS). new LIST 01- DUTCH ACAEI ^ II. 



1834. Gamasus cossi Dug. in Ann. Sc. Nat, (2) II, p. 19, 26. 



1844. Gamasus cossi Gerv, Apt. Ill, p. 219. 



1880. Gamasus cossi Haller, Mrlb. Paras. Wirb. p. 28, 33. 



188i. Gamasus cossi R. Can. in Bull. Soc. Ven. Trent. Sc. 

 Nat. II, I, p. 159. 



1882. Laelaps sp. Beri, in Bull. Soc. Ent. Ital. 14, p. 350. 



NB. Non Dermanyssus Richardii Can. et Fanz. ! 



Lyonet has found numerous mites on the caterpillar of Tf^^ÄMM* 

 cossus (L.). By the zealous care of Mr. W, de Haan of 's-Gra- 

 venhage, Lyonet's unedüed manuscripts were published in 1829 and 

 1830 in the Mémoires du Museum d'Histoire Naturelle de Paris, and 

 in 1832 separatein one Volume. Lyonet's drawings and descriptions 

 are sufficient to recognize the animal. Tliough Ant. Dugès has 

 named the animal, and thougli further Gervais, Haller, Canes- 

 trini and Berlese mention it, nobody has ever seen it again. 



In 1899 I received from Mi\ A. A. van Pelt Lechner, Burgo- 

 mastei' of Zevenhuizen, near Gouda, an acarus found by him on 

 a caterpillar of Trypanus cossus (L ). I believe this animal to be 

 the real Pou de la chenille du hois de saule of Lyonet. The likeness 

 of Lyonet's figure and mine is striking. 



A «ligne» — 2166 n.\ Lyonet says his animal was «un bon 

 quart de ligne», that is at least 542 |i^. , my animal measures 

 570 «. Moreover Lyonet's description fitts too. 



Kleemann has found mites on caterpillars of Bonibyx Hera, 

 much smaller than those of naked caterpillars. I think that 

 Kleemann saw larvae , or protonymphae , of Tyroglyphis longior Gerv, 

 This mite is found under bark of trees, among decaying leaves, 

 in champignons, etc. I consider Lyonet's «Pou d'une chenille» 

 {jiastfoiìacha rubi) described and figured in Mém. Mus. 19, 

 p. 371, tab. 24, fig. 16, and in his Rech. s. I'anat. et les métam. 

 de diff. esp. d'Insectes, 1832, p. 249, also a larva of Tyroglyphus 

 loìigior Gerv. 



Kleemann's mites of naked caterpillars may, however, have been 

 Hyjjoaspis cossi (Ant. Dug.) too, 



I have found a specimen in May 1900, on Lacerta agilis L. 



