122 Notes on Acari parasitic on Birds. 



received through the kindness of Mi - . G. A. Bedford, of the 

 Union Veterinary Station. 



Pterolichus bicaudatus, Gerv. 



Nymph (second stage). Posterior plate of dorsum roughly 

 triangular or elongate heart-shaped in outline, the apex 

 pointing forwards ; posterior margin of this plate indented in 

 the middle ; its surface is finely and evenly punctated. 



Host. South African ostrich. I have examined specimens 

 of this species from Sterkstroom, Cape Colony, and from 

 California. 



Liponyssus silviarum, Can. & F. 



Dermam/ssus sikiarum, Canestrini and Fanzago, Atti R. Inst. Venet. 



1877-1878, (5) iv. p. 124. 

 Leiognathus silviarum, Canestrini, Prospett. Acarof. Ital. 1885, i. p. 121. 

 ? Lophoptes patavinus, Mcgnin, C. R. Soc. Biol. 1891, iii. 

 Liponyssus canadensis, Banks, Washington, Proc. Ent. Soc. 1909, xi. 



p. 134. 



This species occurs both on sparrows and poultry in the 

 United States, and this is of some interest, for the species 

 has not hitherto been recorded as a parasite of poultry 

 (unless Megnin's Lophoptes patavinus is the same species). 

 It differs from the very closely allied species L. bursa princi- 

 pally in having only one pair of long hairs at the extreme 

 posterior end of the dorsal scutum, whereas in L. bursa there 

 are always two quite long pairs of hairs in this position. 



Hosts and localities. I have examined specimens from 

 poultry from the following localities : — Harvel and Raymond, 

 Illinois; Lafayette, Indiana; Aberdeen, South Dacota; 

 Beltsville, Maryland ; Washington, D.C. It occurs on 

 sparrows in the following localities : — Raymond, Illinois ; 

 Aberdeen, South Dacota ; Dallas, Texas. In the British 

 Museum there are specimens from Russia found on Motacilla 

 alba, and others from the Zoological Gardens (on European 

 sparrow-hawk and Indian jay). 



Liponyssus bursa, Berlese. 



Additional localities. Gharbia Province, Lower Egypt ; 

 two lots of this species from domestic poultry, collected 

 autumn 1918 by Mr. Aghion. Dallas, Texas ; on English 

 sparrow (F. C. Bishopp). 



