32 IXODOIDEA, OR TICKS, OF THE UNITED STATES. 



Ixodes marxi n. sp. (PL IX, fig. 8.) 



Female. — Shield, capitulum, and legs pale yellowish gray. Ca- 

 Ijitulum (PL III, fig. 10) rather broad, the posterior angles hardly 

 projecting; porose areas somewhat circular, far from sides, and 

 nearly their diameter apart; palpi with last joint fully as long as 

 broad, plainly shorter than the second. Shield (PL III, fig. 10) 

 about one and one-half times as long as broad, broadest much before 

 middle, narrowed behind, with concave sides, ti]) broadly rounded, 

 lateral carinse practically invisible, surface very finely and rather 

 sparsely punctate. Abdomen with fine punctures and very short 

 hairs; stigmal plate very small, nearly circular, surface granulate; 

 coxae (PL III, fig. 10) almost unarmed, but a small tooth behind on 

 coxse I and II and a short spine at base of coxa I ; legs rather short, 

 tarsi suddenly narrowed before tip. 



Length of female shield, 1 mm. 



I have seen this species from Washington, D. C. ; Salineville and 

 Wauseon, Ohio ; Ithaca, N. Y. ; Portland, Mich. ; Guelph, Ontario, 

 Canada; and Denver, Colo. It has usually been taken on red squir- 

 rels, but the specimen from the last locality was from fox. Two of 

 these specimens were referred doubtfully by Neumann to his va- 

 riety incJioatus of Ixodes hexagonus, which, however, has an earlier 

 name in /. eanisuga Johnston, 1849, a common dog tick in Scotland. 

 Through the kindness of Dr. William Evans I have obtained speci- 

 mens of /. eanisuga and find that it has a more coarsely punctate 

 shield than our species, and the porose areas are larger, Avhile the 

 legs are larger and there is no trace of a spine at base of coxa I. I 

 have not seen the male of /. marxi. I name it in honor of Dr. George 

 Marx, who had recognized its distinctness and given it a manu- 

 script name. 



Genus HJEMAPHYSALIS Koch. 



Venter showing a curved groove behind the anus, and from this a 

 median furrow back to margin of body. Capitulum not angulate on 

 sides; porose areas large, longitudinal, distant. Palpi short, second 

 joint with an acute basal prolongation outward. Shield without 

 markings ; no ocelli. Abdomen showing festoons behind ; coxa I with 

 one tooth behind ; coxa IV of male not enlarged. No anal plates in 

 male. Stigmal plate broad, with a small outer point. Tarsi II, III, 

 and IV indistinctly divided, the basal part shorter than the apical 

 part, and no tooth-like claw at apex. 



Type. — H. concinna Koch. 



I have seen but two species from our territory; the record of 77. 

 concinna is due to wrong synonymy. 



