262 
Hominoxious A rthropods 
gg. With eyes. 
h. Anal groove distinct; posterior marginal festoons present, 
i. Base of the capitulum (fig. 150c) rectangular dorsally; 
usually ornate.Dermacentor Koch. 
j. Adults with four longitudinal rows of large denticles on 
each half of hypostome; stigmal plate nearly circular, 
without dorso-lateral prolongation, goblets very large, 
attaining 43/* to 115/^ in diameter; not over 40 per 
plate, each plate surrounded by an elevated row of 
regularly arranged supporting cells; white rust want¬ 
ing; base of capitulum distinctly broader than long, 
its postero-lateral angles prolonged slightly, if at all; 
coxae I with short spurs; trochanter I with small 
dorso-terminal blade. Texas, Arizona, etc. D. nitens 
151. Rhipicephalus bursa, male. 
After Nuttall and Warburton. 
jj. Adults with three longitudinal rows of large denticles on 
each half of hypostome; goblet cells always more 
than 40 per plate; whitish rust usually present, 
k. Dorso-lateral prolongation of stigmal plate small or 
absent; plates of the adults distinctly longer than 
broad; goblet cells large, usually 30/u to 85M in 
diameter, appearing as very coarse punctations on 
untreated specimens, but on specimens treated 
with caustic potash they appear very distinct in 
outline; base of capitulum distinctly (usually about 
twice) broader than long, the postero-lateral angles 
distinctly produced caudad; spurs of coxae I long, 
lateral spur slightly longer than median; tro¬ 
chanter I with dorso-terminal spur. D. albipictus, 
(= variegatus), salmoni, nigrolineatus. 
