270 
Hominoxious Arthropods 
kk. Anal opening below. 
I . Pedicel of the suckers jointed; mandibles styliform 
and serrate near the tip . Psoroptes Gerv. 
P. communis ovis is the cause of sheep scab. 
II . Pedicel of the suckers not jointed; mandibles 
chelate. 
m. No suckers on the legs of the females; parasitic 
on birds, including chickens. C. mutans is 
itch mite of chickens. Cnemidocoptes Furst. 
mm. Suckers at least on legs I and II; parasitic on 
mammals. 
n. Legs very short; in the male the hind pairs 
equal in size; body usually short . 
. Sarcoptes Latr. 
S. scabiei is the itch mite of man (fig. 56). 
157. Amblyomma, female. After Nuttall 
and Warburton. 
nn. Legs more slender; in the male the third pair 
is much larger than the fourth; body more 
elongate. 
o. Female w r ith suckers on the fourth pair of 
legs. Species do not burrow in the skin, 
but produce a scab similar to sheep scab. 
They occur in the ox, horse, sheep and goat 
.Chorioptes Gerv. 
C. symbiotes bovis of the ox has been 
recorded a few times on man. 
00. Female without suckers to the fourth legs, 
p. Hind part of the male abdomen with two 
lobes. On a few wild animals . 
. Caparinia Can. 
