]^26 PROCEEDINGS OF THE NATIONAL MUSEUM VOL. 106 



16. Nonspecialized setae of leg I with numerous, fine, curved setules. 



Scutum with strong ridges anterior to each pseudostigma, pseudo- 

 stigmata deeply recessed 17 



Nonspecialized setae of leg I with rather few, heavy, straight setules. 

 Scutum plain, or with ridges not strongly indicated, no deeply de- 

 pressed areas {"luteodema" group) 18 



17. Lateral seta on palpal tibia with one or two thin setules (or nude, 



Brennan, 1948) 14. E. criceticola Brennan 



Lateral seta on palpal tibia strongly pectinate . 15. E. calif ornica (Ewing) 



18. No genuala II or III 16. E. luteodema Brennan 



Genuala II and III present 17. E, marmotae, new species 



19. AL's and PL's long, about 70-80 microns, and about the same length; 



scutum roughly rectangular 18. E. hamiltoni Brennan 



AL's much shorter than PL's; scutum tends to be pointed at postero- 

 lateral corners {"blarinae" group) 20 



20. Posterior dorsal setae leaflike, broad and thin with small setules on 



surface away from body 21 



Posterior dorsal setae with round shaft with setules grouped around it 22 



21. About final three rows of dorsal setae flattened; range southern. 



20. E. carolinensis, new species 

 Flattened setae confined mostly to final dorsal row; range northern. 



21. E. ohioensis, new species 



22. Scutum and leg segments distal to coxae with punctae 23 



Scutum and leg segments distal to coxae without punctae 24 



23. Cheliceral base with punctae; galeal setae strong with setules along 



opposite edges 22. E. crateris, new species 



Cheliceral base without punctae; galeal setae branched. 



19. E. blarinae (Ewing) 



24. Head of sensilla cordiform; cheliceral base without punctae; range 



western 24. E. sciuricola (Evv'ing) 



Head of sensilla ovoid; cheliceral base with fine punctae; range eastern. 



23. E. setosa (Ewing) 



The "lacerta' group 



The ''lacerta" group consists of E. lacerta and E. bigenuala. 

 The group is unique in the genus. The mites are very small. Body 

 striae are fine. The anus is farther posterior than usual. Punctae 

 on the cheliceral base are confined to the posterior portion. The 

 number of body setae is reduced and the setae are small with fine 

 setules. The nonspecialized setae of palps and legs are small with 

 relatively few, fine setules. Tibia I has eight nonspecialized setae. 

 The tarsi have fewer nonspecialized setae than usual, tarsus I 

 having about 19 or 20, and tarsi II and III about 13 or 14. Sub- 

 terminala and parasubterminala I are lacking. There are no 

 genualae II and III. The general shape and character of the scuta 

 of the two species in the group are similar. The pseudostigmata 

 are set in the bases of short ridges which bound them antero- 

 medially. 



