MITES OF SUBFAMILY HAEMOGAMASINAE — KEEGAN 245 



pairs of smaller setae, one smaller seta between tliem. Setae of apical 

 region larger than on remainder of shield; about 45/a in length and 

 9fi to 45/x apart; all setae on shield smooth. Setae of unprotected 

 dorsal integument larger than those on shield, especially at posterior 

 body margin ; all are smooth. Lacinae of tritosternum smooth. Pre- 

 sternal area sculptured; sutures with tiny, posteriorly directed spines; 

 in contact with slightly more than median third of the anterior mar- 

 gin of sternal shield. Posterior margin of sternal shield invaginated 

 to a level about midway between posterior and middle pairs of usual 

 sternal setae. Anterior pair of sternal setae on anterior margin of 

 shield at junction of its lateral and median fourths; middle and pos- 

 terior pairs of setae not on lateral margins of shield; middle pair of 

 setae at least once and a half as far from posterior as from anterior 

 pair, which are the smallest of the three. Anterior pair of sternal 

 pores nearly parallel with another margin of shield. Genitoventral 

 shield sculptured; relatively narrow; only slightly expanded pos- 

 teriorly ; usually about as wide as distance between coxae IV ; acces- 

 sory setae much smaller than usual genitoventral setae and distinctly 

 posterior to the latter ; in a series of 36 specimens numbers of acces- 

 sory setae varied from 19 to 41. Only one specimen had more than 27 

 setae, and most possessed between 21 and 26; mean number in the 

 series was 23.5. The anterior setae are slightly larger than those at 

 the posterior margin of the shield ; almost all setae are in posterior 

 half of shield ; all are smooth. Anal shield not quite as long as it is 

 wide ; in all but two of the specimens examined seven accessory setae 

 and three usual anal setae were present. Accessory anal setae about 

 as large as usual setae, although the most anterior accessory setae may 

 be smaller than the others. Unpaired, usual anal seta is at posterior 

 margin of shield proper and is largest seta on shield ; all are smooth. 

 Anus almost entirely in posterior half of shield. Metapodal shields 

 irregular, almost always longer than wide. Endopodal shields pres- 

 ent. Tubular portion of peritreme extends to posterior half of coxae 

 II, posterior end of peritreme fused with fovea of coxa IV; of dis- 

 tinctive shape. Metasternal setae smooth and as large as posterior 

 pair of sternal setae. A pair of longitudinal pores slightly anterior 

 to bases of these setae. Ventral body setae larger than those of dorsal 

 shield, especially at posterior body margin ; all are smooth. Epistome 

 narrow ; with 7 to 10 usually simple, lateral fimbriae on each side and 

 four or five branched distal fimbriae. Both chelae toothless ; of about 

 equal length. Movable chela may be slightly larger. Fixed chela 

 nearly straight but gently curved in its distal third ; terminates in a 

 point, which may be filamentous, and bears a pilus dentilis at its base. 

 Movable chela wider, rodike, terminating in a blunt tip, and grooved 



