264 
Hominoxious Arthropods 
j. No ventral plate or shield in either sex (fig. 153). R. 
bicomis from the United States ... Rhipicentor Nuttall 
jj. Males with a pair of adanal shields, and usually a pair of 
accessory adanal shields. Numerous species, among 
them R. sanguineus (fig. 154) and texanus, the latter 
from the United States. Rhipicephalus Koch 
hh. Anal grooves faint or obsolete; no marginal festoons. 
i. Short palpi; highly chitinized; unfed adults of large size; 
coxae conical; male with a median plate prolonged in two 
long spines projecting caudad; segments of leg pair IV 
greatly swollen (fig. 155, 156). M. winlhemi . 
. Margaropus Karsch 
152 . Monieziella (Histiogaster) emtomophaga-spermatica, ventral aspect, 
male and female. After Trouessart, 
ii. Very short palpi, ridged dorsally and laterally; slightly 
chitinized; unfed adults of smaller size; coxae I bifid; 
male with adanal and accessory adanal shields (fig. 139). 
B. annulatus.Boophilus Curtis 
ff. Palpi longer than broad (fig. 157). 
g. Male with pair of adanal shields, and two posterior abdominal 
protrusions capped by chitinized points; festoons present or 
absent. Several species, among them H. aegypticum (fig. 140) 
from the old world.Hyalomma Koch 
gg. Male without adanal shields but small ventral plaques are 
occassionally present close to the festoons. Many species, a 
few from the Unted States (fig. 157). . . . Amblyomma Koch 
h. Coxa I with but one spine; metatarsi (except 1 ) with two 
thickened spurs at tips . A. maculatum 
hh. Coxa I with two spines; metatarsi without stout spurs at 
tips, only slender hairs. 
