ART. 13. DERMANYSSID MITES OF NORTH AMERICA——-EWING. 9 
DESCRIPTIONS OF NORTH AMERICAN SPECIES. 
Genus ENTONYSSUS Ewing. 
ENTONYSSUS HALLI, new species. 
Female.—A medium-sized, light-brownish gamasoid. Palpi mod- 
erate, of generalized type, a few minute spinelike setae at tip, the 
one on the inside being the largest; chelicerae moderate, fixed arm 
harpoonlike, with a sharp point and a distal, backwardly directed 
barb, movable arm not extending to the tip -f fixed arm and shaped 
like the claw of a hawk. Dorsal shield large and undivided. Stig- 
mata situated ventrolaterally above and behind the third coxae. 
Sternal plate large and reaching to the posterior margin of third 
coxae. Anal plate large and extending to the posterior margin of 
abdomen. Legs similar in shape, the posterior pair being the long- 
est; tarsus of leg I about twice as long as tibia; claws of all the 
legs stout and strongly curved at their base but with their distal part 
tapering to a fine sharp point. Length, 0.69 mm.; width, 0.41 mm. 
Male.—Unknown. 
Type locality.—(*) 
Holotype.—Cat. No. 24748, U.S.N.M. 
Described from holotype specimen taken from air sac of Pine snake 
at National Zoological Park by Dr. M. C. Hall on October 14, 1908. 
Two or three other specimens were taken, but these were practically 
destroyed in the process of preparation. One of them is on slide 
with type. 
Genus IXODORHYNCHUS Ewing. 
IXODORHYNCHUS LIPONYSSOIDES, new species. 
A stout brownish species, with the sides of the body about parallel. 
Palpi moderate, filiform. Chelicerae not large but heavily chitinized, 
three recurved hooks present, the proximal! being the largest and 
the distal smallest, arm of chelicera longer than the distal segment 
from which is springs. Dorsal shield entirely covering the body and 
divided by a transverse suture into two subequal parts. Peritreme 
long, sinuous, and extending beyond the anterior coxae. Sternal 
plate large, reaching third coxae. Anal plate oval, with anus 
situated centrally. Legs short, stout, subequal; tarsus of leg I about 
one and a half times as long as the tibia, the latter being almost as 
broad as long; patella of leg I with four long, stout spines above; 
femur with two similar but even larger spines. Length, 0.63 mm.; 
width, 0.44 mm. 
Type locality —Madrid, Iowa. 
Type slide.—Cat. No. 24744, U.S.N.M. 
Described from various cotypes mounted on five different slides. 
All specimens collected by M. F. Boyd from eye of snake at Madrid, 
