18 PROCEEDINGS OF THE NATIONAL, MUSEUM vol. 80 : aht. 8 



Type host. — California pocket mouse {Perognathus californicus 

 caXifomicus). 



Type locality. — Berkeley, Calif. 



Type sZ«We.— U.S.N.M. No. 1027. 



Eight specimens at hand, received from S. B. Benson, October 1, 

 1929. This species differs from all other chiggers known to the 

 writer in the form of its chelicerae and in the number of dorsal 

 abdominal setae present. 



HANNEMANIA PENETRANS, new species 

 Plate 3, Figtjbe 4 



Palpi rounded laterally; first, second, and third setae simple, sec- 

 ond equal to first in length, third much shorter. Palpal thumb small, 

 inconspicuous. Palpal claw short, very sharp, trifurcate; middle 

 prong the stoutest and longest; accessory prongs subequal. Cheli- 

 cerae but slightly curved, each ending ventro-distally in a flattened 

 spearhead, which is irregularly serrate on outer margin, basal process 

 conspicuous and armed with three teeth on postero-dorsal aspect. 

 Dorsal plate broader than long and posteriorly outwardly curved; 

 submedian setae shorter than the antero-lateral, the latter shorter 

 than the postero-lateral. Pseudostigmata situated behind a line 

 drawn between the pair of postero-lateral setae, each about equal dis- 

 tance from the other pseudostigma and the postero-lateral seta on its 

 own side ; one pair of slits present, these being straight, diagonal, and 

 situated just behind the pseudostigmata; pseudostigmatic organs 

 short, simple. Dorsal setae about 20. Legs rather short; tarsus I 

 with very sharp dorsal spine situated about its length from the base 

 of the segment, subapical seta setiform, not situated on a tubercle, 

 and extending to the base of the tarsal claws. 



Length of partly engorged specimen, 0.81 mm. ; width, 0.49 mm. 



Type host. — Leopard frog (Rana pipien^s). 



Type locality. — Great Falls of Potomac, Va. 



Type slide.— U.^.'^M. No. 1028. 



Described from eight specimens; two taken from a green frog 

 {Rana clamitatis) , collected at the type locality September 21, 192G, 

 by the writer; four taken from leopard frogs {Rana pipiens), at type 

 locality, August 27, 1930, by H. E. and Paul Ewing; and two from 

 same host and locality, September 24, 1930, by same collectors. This 

 species is nearest to H. eltoni Sambon but has the palpal claw trifur- 

 cate and short pseudostigmatic organs. 



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