46 IXODOIDEA, OR TICKS, OF THE UNITED STATES. 



sjiecies, Neumann later made it a variety of D. electus {variahilis), 

 but it differs in many important characters from that species, and the 

 granuhitions of the stigmal plate are much larger. 



Dermacentor parumapertus var. marginatus n. var. 



This form agrees in general with the true D. 'parwmapeTtus ^ but 

 differs in several minor points. The posterior border of the female 

 shield (PL VIII, fig. 6) is margined with white; the porose areas 

 are larger and rather closer together; the lateral lobes of the shield 

 have fewer punctures, and the shield is more contracted behind the 

 eyes; the stigmal plate of the female (PI. VIII, fig. 0) has a narrowei- 

 dorsal prolongation, and the inner margin is more convex; the 

 posterior angles of the cai^itulum (PI. VIII, fig. G) are less promi- 

 nent. Otherwise it is very similar to the type. 



Several specimens from Mesa City, Ariz., from a jack rabbit 

 (Cordley). 



Dermacentor venustus n. sp. 



Male. — Red-brown, marked with white, but not so extensively as 

 in D. occidentalism, usually but little white on the middle posterior 

 region; legs paler red-brown, tips of joints whitish. Capitulum 

 (PI. VIII, fig. 5) quite broad, its posterior angles only slightly pro- 

 duced ; palpi very short and broad, not as long as width of capitulum. 

 Dorsum about one and tAvo-thirds or one and three-fourths times as 

 long as broad, with nuiny, not very large, punctures; lateral furrows 

 distinct. Legs of moderate size, hind pair plainly larger and heavier, 

 and with the teeth below distinct. Coxae armed as usual, the coxa 

 IV (PI. VIII, fig. 4) nearly twice as wide at base as long. Stigmal 

 plate (PI. VIII, fig. 5) with a rather narrow dorsal prolongation, 

 with large granules on the main part and minute ones on the pro- 

 longation. 



Length of male, 3.5 to 5 mm. 



Female. — Capitulum and legs reddish brown, the latter with tips 

 of joints M'hitish ; shield mostly covered with white — this white not 

 so much broken up by the brown dots as in D. occidentalh; abdomen 

 red-brown. Capitulum (PL VIII, fig. 5) rather broad, posterior 

 angles but little produced, the porose areas rather large, egg-sha23ed, 

 nncl quite close together; palpi shorter than width of capitulum. 

 Shield (PL VIII, fig. 7) as broad as long, broadest slightly before 

 the middle, and rather pointed behind, with numerous, not very large 

 punctures. Legs of moderate size, the coxse armed as usual. The 

 stigmal plate (PL VIII, fig. .5) has a rather narrow dorsal j^rolonga- 

 tion, with large granules on the main part, and small ones on the 

 prolongation. 



Length of female shield, 2 mm. 



