VARROA JACOBSONII. 221 



nialae, aud minute rudimeutal inner malae, between which 

 there is a deep cleft. This however, is a mystification, for 

 if we dissect the head aud observe it from aside, we 

 see that the hypostome consists of the same parts as 

 usual, only with another configuration, the result of the 

 changed manner of living. We distinctly discern (fig. 9) 

 the long flat transparent horns or outer malae (invisible 

 on a ventral aspect) apt to pierce; further the thick well 

 chitinized inner malae, crooked downward and veutrally 

 provided with minute teeth directed backward, thus being 

 an excellent sawing- and fixation organ, and simulating, 

 though 'in rudiments, the beautiful rasp-shaped hypostome 

 of Ixodidae ; aud finally the tongue or lingua, perfectly 

 smooth, without any trace of fine hirsuteness, on the con- 

 trary more being an organ apt to pierce than one to lick. 

 Palpi filiform, equal in thickness throughout, short, for the 

 rest normal ; dorsally (fig. \) the trochanter is bare, the femur 

 provided with only one central hair directed inward and 

 curved forward. Veutrally the trochanter (fig. 8) with 

 only one distal and inner hair; femur and genu bare, 

 without cleaning-materials; tibia normal, tarsus normal; 

 only the so-called fork or comb is bidentate (fig. 10) aud 

 cue of its teeth is small. 



If we now imagine that the two mandibles take a more 

 ventral situation, and place themselves between the two 

 horns and above the tongue, and that the horns or outer 

 malae touch each other above the so unusually placed 

 mandibles, we may fancy how originated the well known 

 rostrum of the Ixodidae. 



Legs. All the legs are shorter than half the length 

 of the creature and rather thick. It may be that legs IV 

 including the sucker are somewhat longer. Legs I are the 

 shortest and narrowest; the other ones increasing slightly 

 in length and thickness. Dorsally the legs (fig. 1) are rather 

 hairy, being provided with two rows of hairs (like in the 

 parasitical Spinturnicinae). Only the legs I and II are pro- 

 vided with the lateral rows. Legs I, II and III are also 



Notes from tlie Leyden JMuseura, Vol. XXIV. 



