CLASSIFICATION AND HABITS OF TICKS. 41 
Dorsal surface of capitulum rectangular, sides straight; male without anal plates. .4 
. Second and third palpal segments extend laterally into sharp points; stigmata 
fay eenyal ses SC Ra eA ae Riel i ene a aero Genus Margaropus (p. 49). 
Second and third palpal segments even; stigmata comma-shaped. 
Genus Rhipicephalus (p. 47). 
4. Eyes present; external border of palpi straight; coxee I bidentate. 
(oN) 
Genus Dermacentor (p. 49). 
Eyes absent; external border of palpi uneven; coxe I not bidentate. 
Genus Hemaphysalis (p. 52). 
Subfamily Ixopin#. 
5. Anal groove surrounds anus anteriorly and opens posteriorly; eyes absent; stigmal 
plate Mean yeCwreWlars ko. aaa ae hein ae a. 2 en = = Genus Ixodes (p. 54). 
Anal groove surrounds anus posteriorly and opens anteriorly; eyes present; stigmal 
FULD MSOs ey. LORI a tpt os ier ae ee cera ee Genus Amblyomma (p. 58). 
Lahille has recently ® published an ingenious graphic table for the 
separation of the families and genera of Ixodoidea. It is reproduced 
SuB-ORDEN: ARPAGOSTOMA 
SaaS Apoes 
Argaside ant a aan 
Heo PRIOR sr ARs Hee maphysalis” 
SGERe ee ; 
~Neumannielia 
Amblyomma * 
FAMILIAS 
Anopli oe al 
Cat CaP lois | Oe Oe Dermacentor * 
| Hyalomma 
pe Ae Mia © “s @e Rhipicephalus” 
ae ; 26 @---Boophilus’ 
eis DN AOE S 
Per ssoph — 
Se \Anommata, PA) ee E schatocephalus 
‘Ge a 
_ Ceratixodes’ 
fig. 2.—Graphie table for the separation of the families and genera of ticks. (From Lahille.) The 
underscored genera are represented in the United States. 
lxodide 
here as figure 2. The genera underscored are known to be repre- 
sented in the United States. The suborder Arpagostoma of Lahille 
is the same as the superfamily Ixodoidea of Banks, used by us. 
Family ARGASIDZ. ' 
The family Argaside is represented by two genera, Argas and 
Ornithodoros. They are readily distinguished by the characters 
given in the table. ate species are peuoalae on imanabaals and birds. 
Gye iene Argent., 1905, p. a1, 
