552 IVAR TRAGARDH 



length of the claws — semicifcular on ventral view ; subunguinal 

 caruncle heart-shaped, fused with the supraunguinal one to 

 a large sucker» 



Gnathosoma.Epist orna (fig. 47). Tlie médian mucroisstron- 

 gly chitinous, shorter than in Oudeman's spécimens (compare 

 1903, pi. 5, fig. 18) ; the teeth in the middle of the latéral edges 

 vary in number and shape on both sides. Mandibles (fig. 48) 

 according to 0. of the same shape as in the female, as described 

 by MiCHAEL. Michael's description and drawings, although 

 excellent for the time they were published, are, however, not 

 quite so detailed as one could wish for now when the rapidly 

 growing number of acari renders a higher magnifying necessary. 

 M. evidently did not attach so much weight to their shape, 

 since he says « Mandibles with both limbs of chela of about 

 equal length, crossing at their ends, with about six teeth 

 on each chela ». This statement is true as regards the upper 

 jaw of the mandible delineated by M. The shape of the lower 

 jaw it is impossible to see, as it is partly covered by the upper 

 one, only two teeth being visible, besides the terminal one. 

 Unless OuDEMANS has seen Michaels' spécimens, it is difficult 

 to see how he has been able to get an accurate idea of the shape 

 of the mandibles of the female. 



As a matter of fact, the lower jaw has only 4, but the upper 

 one no fewer than 7 teeth. 



The lower jaw is slightly shorter than the upper one, with 

 an exceedingly little convex ventral edge, with longer and less 

 sharply curved terminal tooth. In the distal half 3 equidistant 

 teeth which increase slightly in height in their backward succes- 

 sion, and at the same time point more backwards ; behind 

 the posterior one the edge is even ; the edge between the ter- 

 minal and the one next to the terminal tooth has a dense row 

 of extremely minute teeth. 



The upper jaw. The dorsal edge is slightly concave a 

 little behind the pilus dentarius; there are in ail 7 teeth, 

 increasing in size in their order backwards as far as the fiftli 



