378 ON NEW OR LITTLE-KNOWN ACARI, 



Pygmephorus pilosus Oudmns. 



5 . First tai^sus not produced nor enlarged. The second 

 striated sensory hair (from the distal end) is much larger and 

 stouter than the others, the first being of moderate length and 

 slender ; the two proximal sensory hairs are quite short, one of 

 them is slender but club-shaped, the other very slender, straight, 

 and cylindrical. 



Second tarsus with a rather long spine in the middle of the 

 dorsal surface, and with a short spine and also a short club- 

 shaped sensory hair near the proximal end. Claws of this leg 

 slender and not bifurcated. Pseudostigmata rounded distally 

 (not pointed). Hairs of body and limbs more distinctly feathered 

 than in P. tarsalis. 



Habitat. Arvicola agrestis and Talpa eurojxea, England ; several 

 specimens off these hosts. 



Acarapis, gen. nov. 



I propose the new generic name Acarapis for Tarsonemus woodi 

 Rennie, 1921, the principal structural differences between this 

 new genus and Tarsonemus being as follows : — Anterior leg of 

 larva of Acarapis well-developed and furnished with a pair of 

 claws and a pulvillus, but the second and third legs are very 

 short (almost rudimentary) and without either claws or pulvillus. 

 (In Tarsonemus the larval stage has all three pairs of legs well- 

 developed and all end in claws and pulvillus.) The globular 

 pseudostigma always present between the first and second legs in 

 the females of Tarsonemus is absent in Acarapis. Fourth leg of 

 female shorter and stouter than in Tarsonemus, and furnished 

 with a larger number of hairs, resembling Scutacarus in this 

 respect. 



