CLASSIFICATION AND BABIT8 OF TICKS. 
41 
Dorsal Burface of capitulum rectangular, sides straighl ; male ^ithoul anal plat< 
:'». Second and third palpal Begmehts extend Laterally into sharp points; stigmata 
aearly circular < renus Ifargaropus I p, 19 i. 
Sccmd and third palpal Begments even; stigmata comma-shaped. 
( ieiiu< Rhipia /'/ml us p. 47). 
■I. Byes present; externa] border of palpi straight; coxae I bidentate. 
( renus Di rmaa ntor p. 49 1. 
Byes absent; external border of palpi uneven; coxae I nol bidentate. 
I renus //.-' urn physalis 1 1 1 
Subfamily [xodin i . 
5. Anal grocj e surrounds anus anteriorly and opens posteriorly ; eyes absent; stigma! 
plate nearly circular < renus Ixodes i p. 5 I . 
Anal groove Burrounds anus posteriorly and opens anteriorly; eyee present; stigma! 
plate reniform < renus Amblyomma i p. 58 
Lahille has recently published an ingenious graphic table for the 
separation of the families and genera of [xodoidea. It is reproduced 
Familias 
SUB-ORDEN: ARPAGOSTOMA 
....... Arqas 
U 
Argasidae QJ J g _____ ( Whodoros - 
/ , " <#$ Hrpmaphusalis' 
O $& 1 W - Aponomma * 
Anopli | Anommatd l J% Neumanmella 
^-x i A.' Amblijomnna " 
Ommata \24&k, 
/xodidae/ 
1 
Artiopli 
< ****** 
«3\ 
Ommata 
Perissopli) /Q\ 
'd % |Anommata\ 
Dermacentor • 
$ Hyalomma 
$ C5^ Rhl P lC ^ ohaluS * 
H C% ^-- Boophilus " 
($§'.... - Ixodes * 
^ ..._ EschaLocephalus 
{$.-——:- Ceratixodes* 
Fig. 2. Graphic table for the s parationi fthe familiesand genera cf ticks. (From Lahille.) The 
underscored genera are represented in the United States. 
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 [xodoidea of Banks, used by us. 
Family ARGASID^. 
The family Argasidae is represented by two genera, Argas and 
Ornithodoros. They are readily distinguished by the characters 
given in the table. The species are parasitic on mammals and birds. 
a [xodides Aj-gent., L905, p. 21. 
