Cooley & Kohls: Argasidae of N. America, etc. 23 



depressed areas in a symmetrical pattern; the individual discs have their 

 surfaces only a little changed over the general granulated surface, and are less 

 distinct on the ventral side. 



Hairs. — A few very fine hairs, easily overlooked, arise from some of the 

 tubercles and are more apparent at the anterior end. 



Legs. — Short and heavy. Tarsi II, III, and IV with the subapical dorsal 

 protuberance moderate, negligible on I. Length of tarsus I about 0.48; meta- 

 tarsus about 0.48. Length of tarsus IV about 0.72; metatarsus, about 0.69. 

 Hairs on the legs few, short, inconspicuous. 



Coxae. — Each coxa with an elongated smooth sclerite which, together with 

 deep invaginations on the posterior side mark the position of the coxa. Coxa 

 IV also has such an invagination on the anterior side. 



Hood and Camerostome. — Hood very short and broad — a curved eleva- 

 tion anterior to the mouth parts. Camerostome lined with numerous fine, long 

 hairs. 



Capitulum. — Basis very broad and short, curved, approaching a reniform 

 shape with the convexity behind. 



Palpi. — Short and heavy; article 1 swollen ventrally and laterally; hairs on 

 the palpi fine and long. 



Hypostome. — Vestigial in marked contrast with the well developed hypo- 

 stome of the nymph. Short, broad, with the sides converging anteriorly, con- 

 cave dorsally and convex ventrally; without denticles and with the apical 

 margin curved and thin. Length in the female 0.135. 



Folds. — Coxal and supracoxal folds are present but in well engorged 

 specimens the coxal fold is not much in evidence. 



Grooves. — A short postanal groove present near the posterior end of the 

 body. Median postanal groove present only anterior to the postanal groove, 

 faint. Other grooves are negligible or absent. 



Sexual opening. — At the level of the posterior ends of coxae I. 



Spiracle. — Circular, mildly convex. 



Eyes. — Absent. 



Anus. — Circular, very small. 



SECOND NYMPH 



This tick is ordinarily seen only in the second nymphal stage, which is the 

 stage commonly found in the ears of domestic animals, and is the stage in 

 which the species is most easily distinguished from other ticks. 



Body. — When fully fed a little larger than that of the adult. Shape of fed 

 specimens much as in the adult but with the lateral constrictions a little less 



