ART. 13. DERMANYSSID MITES OF NORTH AMERICA——EWING., 17 
between rim of anus and lateral margins; median seta situated 
slightly more than its length behind rim of anus, and subequal to 
paired setae; anal area extending halfway to base of median seta, 
scobinate. Legs of medium length; anterior pair longer than second 
pair; tarsus I about twice as long as tibia I; third legs apparently 
the shortest. Length, 0.60 mm.; width, 0.88 mm. 
Male.—Unknown. 
Type locality.— Rochester, New York. 
Holotype.—Cat. No. 24747, U.S.N.M. A large female, mounted 
ventral side up near the top of slide selected, only one other large 
female on type slide. 
Seven specimens from wood thrush, type locality, by G. A. Franck. 
Genus LIPONYSSUS Kolenati. 
KEY TO NORTH AMERICAN SPECIES. 
a', Anal plate of female triangular, or almost so; paired setae, or anal setae, situated 
on a transverse line drawn at the posterior rim of anus; anal rim very thick. 
L. triangulus, new species. 
a’. Anal plate of female in no way triangular; paired setae situated in front of a trans- 
verse line drawn at the posterior rim of anus; anal rim not so thick. 
b'. Anus situated less than one-half its greatest diameter from the front margin of 
anal plate. 
c', Rim of anus of uniform thickness and anal setae situated but slightly in front 
OM NOs LeMOMMaATOML OS ANUS... 2 ot. poo mcm epee ocgs a mec L. bacoti (Hirst). 
c?. Rim of anus thicker in front and behind than on the sides, anal setae situated 
considerably in front of the posterior margin of anus. 
L. pacificus, new species. 
b*. Anus situated over two-thirds its greatest diameter from the front margin of 
anal plate. 
c!, At the middle of dorsum of abdomen dorsal shield of female is over one-half 
as broad as body. 
d', Sides of dorsal shield of female converging rapidly on the abdomen and 
tip of same about over anus. 
e'. Dorsal shield of female never more than about three-fourths the width of 
theysephalothorax «63: jeaetyee gy 8 darian ve oad L. americanus Banks. 
e?. Dorsal shield of female practically covering the cephalothorax to behind 
the insertion of second legs........... L. occidentalis, new species. 
d*, Sides of dorsal shield not converging rapidly, and in both sexes the same 
covers most of the body dorsally............... L. canadensis Banks. 
c?, At the middle of dorsum of abdomen dorsal shield of female less than one- 
half as broad as body. 
d', Anal plate broadly and evenly rounded in front; anal setae situated at the 
level of the anterior margin of anus........ L. montanus, new species. 
d?, Anal plate somewhat pointed in front and not at all evenly rounded; anal 
setae situated much behind the level of the anterior margin of anus. 
e1, At its broadest place dorsal shield of female not over one-half as broad as 
cephalothorax........ Laie L. tenuiscutatus, new species. 
e?, At its broadest mince dona ‘auseld 4 aon at least two-thirds as broad 
Bs COpNAlOUMOTAR: te eee ae. ae ps ce cace- cae sds) DEESA “CBerlese) . 
