146 A. C. OUDEMANS. ACARI. 



colour may vary too, being from whitish, over yellovv to pink coloured, especially the legs, 

 which may be from almost colourless to brownish-red. The shape of course is, especially in the 

 females liable to varieties from elongate and a little constricted in the middle of the abdomen, 

 to very big. The length of the hairs is also liable to great variation ; the long hairs of the 

 abdomen may be scarcely as long as the abdomen itself, but in some individuals they are 

 longer than the length of the créature the rostrum included ! The pseudostigmatic organs vary 

 but slightly especially in width, less in shape. The tarsus IV in the maie is the most variable 

 of ail parts of the bôdy. 



Fig. 107 is an exact reproduction of tarsus IV of a maie, delineated by BERLESE in 

 his Acari Myriopoda et Scorpiones Italiani, 1884, fasc. 14, n°. 6. He does not tell us how 

 many times it is enlarged. 



Fig. 108 is an exact reproduction of the cf tarsus IV drawn by MlCHAEL in his British 

 Tyroglyphidae, v. 2, tab. 37, enlarged 225 times, according to the author. 



Fig. 109 — 115 are delineated by me by means of the caméra lucida, ail enlarged on 

 the same scale, viz. 570 times. 



Fig. 109 is taken from a spécimen of New Guinea. 



Fig. 110 of Arnhem, Netherland. 



Fig. in of Vegesack, Germany. 



Fig. 1 1 2 of Vegesack, Germany. 



Fig. 113 of Paris, France. 



Fig. 114 of Buré, France, 

 and fig. 115 of San Remo, Italy. Remark especially the thorn-shaped subtarsal hair! 



What a wide field of inquiry to the partisans of the mutation theory ! 



Anoetus Lorentzi Oudms. 

 (Plate V, fig. 116— 118). 



Anoetus Lorentzi, nov. sp. OUDEMANS in Entomologische Bèrichten, 1905, n° 23, p. 223. 



Patria: New Guinea (Cyclope Mountains). 



Found, 13 April 1903, by Messrs. de Beaufort and Lorentz. 



Hypopus (Fig. 116 — 118). Length 170 — 225 p. Colour white, scarcely with yellowish 

 hue. Shape wide oval; céphalothorax, however, anteriorly wide, with concave anterior edge 

 which again is convex in the middle. Texture smooth, dorsally with numerous pores. Curious 

 is a transversely striated band of weak skin between céphalothorax and abdomen. 



Dorsal side (Fig. 117). Céphalothorax anteriorly wide; anterior edge concave, slightly 

 convex again in the middle; posterior edge concave too, so that the céphalothorax is narrowest 

 in the middle. As the anterior edge of the abdomen is concave too, there exists a more or 

 less lens-shaped band of transversely striated weak skin between céphalothorax and abdomen, 

 which touch each other laterally. Hairs: two pairs of hairs in the middle of the céphalo- 

 thorax, one pair in each half. On the abdomen 6 longitudinal rows of hairs as follows: two 

 marginal rows of 4 hairs each ; two submarginal rows of 2 hairs each far forward ; two sub- 

 median rows of 5 hairs each, diminishing in size backward ; the foremost pair of thèse two 

 rows is the stronçest on the whole dorsal side. 



