MITE'S OF SUBFAMILY HAEMOGAMASINAE — KEEGAN 267 



5. Chelae about equal in length; usual pair of apical setae clearly largest on 



dorsal shield; setae of dorsal shield nearly uniform in size. 



E. liponyssoides (Ewing) (p. 244) 

 Fixed chela distinctly the shorter; usual pair of apical setae little if any 

 larger than others of apical region; large and small setae interspersed 

 on dorsal shield E. 1. occidentalis, new subspecies (p. 255) 



6. Fixed chela with 2 teeth E. horridus (Michael) (p. 235) 



Fixed chela with 1 tooth H. mandschuricus Vitzthum (p. 218) 



Fixed chela toothless ' 



7. Anterior pair of maxillary setae smooth 8 



Anterior pair of maxillary setae barbed 9 



8. One pair of accessory setae on anterior margin of sternal shield; shorter 



branch of movable chela with a bifurcate tip_--H. alaskenis Ewing (p. 218) 

 Accessory sternal setae lacking; shorter branch of movable chela undivided 



E. oudemansi (Hirst) (p. 240) 



9 Posterior peritremal pore on medial margin of peritremal shield. 



E. barberi (Ewing) (p. 249) 

 Posterior peritremal pore on or near lateral margin of peritremal shield. 



E. ambulans (Thorell) (p. 228) 

 10. Coxa I and genu II each with a large ventral spur; ventral shield widest 



at level of coxae II I- spiniger, new species (p. 258) 



Coxa I and genu II without spurs; ventral shield widest posterior to 



coxae IV ^' armatus, new species (p. 261) 



Male specimens of H. avisugus, H. liberiensis, and E. quadrisetaius 

 have never been found. 



LITERATURE CITED 



Banks, Nathan. 



1905. Descriptions of some new mites. Proc. Ent. Soc. Washington, vol. 7, 

 pp. 133-142. 

 Beklese, Antonio. 



1889. Acari, Myriopoda et Scorpiones hucusque in Italia reperta : Mesostig- 



mata, fasc. 52, Nos. 2 and 10. 

 1892. Ideni, pp. 15, 30-45. 



1920. Centuria quinta di Acari nuovi. Redia, vol. 14, p. 166. 

 Ewing, H. E. 



1925. New mites of the parasitic genus Haemogamasus Berlese. Proc. Biol. 



Soc. Washington, vol. 38, pp. 137-144. 

 1933. New genera and species of parasitic mites of the superfamily Para- 

 sitoidea. Proc. U. S. Nat. Mus., vol. 82, art. 30, 14 pp., 4 pis. 

 Ewing, H. E., and Stovee, A. J. 



1915. New parasitic mites (Acarina). Ent. News, vol. 26, pp. 10^114. 

 Hill, M. A., and Gordon, R. M. 



1945. An outbreak of dermatitis amongst troops in North Wales caused by 

 rodent mites. Ann. Trop. Med. and Parasit., vol. 39, No. 1, pp. 46-52. 



Hirst, S. 



1914. Preliminary list of the Acari occurring on the brown rat in Great 

 Britain. Bull. Ent. Res., vol. 5, pp. 119-124. 



1916. Notes on parasitic Acari. Journ. Zool. Res., vol. 1, pp. 59-81. 

 Keegan, H. L. 



1946. Six new mites of the superfamily Parasitoidea. Trans. Amer. Micr. 

 Soc, vol. 65, No. 1, pp. 60-77. 



