Cooley dc Kohls: Argasidae of N. America, etc. 121 



with a few scattered, long barbed hairs. Palpi of moderate length; article 1 

 ciosely appressed on the base of the hypostome; articles 2, 3 and 4, free. 



Hypostome. — Short, broad, and rounded apically; convex ventrally and 

 concave dorsally ( scoop- 1 ike ) ; with very fine teeth on the anterior lateral 

 margins (better seen in a balsam mount under a microscope). 



Chelicerae. — Very large and effective. 



Folds. — Coxal and supracoxal folds present. 



Grooves. — The transverse postanal groove present, short; all others indefi- 

 nite or absent. 



Spiracles. — Spiracles an oval, globular protuberance, free on all sides 

 except at the smaller attached end. 



Sexual opening. — At the level of the intervals between coxae I and II. 



Anus. — Very large, in an elliptical frame. 



MALE 



Body. — Length about 4.44; greatest width (at the spiracles) about 2.75. 

 Color light tan. Some specimens are as small as 4.0 x 2.57 (Mcintosh) . Shape 

 pyriform, tapering in front to a point which is bent ventrad. 



Dorsal surface in general flattened and marginated as in the female, and 

 with mild sub-marginal grooves which unite in front but lacking both the 

 excavations in the margins at the sides behind the middle and the deep mar- 

 ginal furrows near them. 



Tubercles — As in the females, 'but with the hairs absent or few in number. 



Discs. — Essentially as in the female. 



Legs. — Legs shorter and larger than in the female; tarsi shorter and with 

 well-developed ventral spurs (absent in the female). Length of tarsus I, 0.45; 

 metatarsus, 0.57; length of tarsus IV, 0.54; metatarsus, 0.66. 



Coxae. — As in the female. 

 Hood. — Absent as in the female. 



Cheeks. — Cheeks absent; finger-like projections near the position of cheeks 

 smaller and fewer in number than in the female. 



Grooves, folds, spiracles, and anus essentially as in the female. 



Sexual opening. — Placed between coxae I (a little anterior to its position 

 in the female) . 



NYMPH 



With many specimens of all stages before us the sexes as well as the late 

 stage nymphs which are to become either male or female are readily separable. 

 Thus we have in this species nymphs which we may speak of as pro-male or 

 pro-female. Their potential sex is indicated by their size, shape, relative length 

 over width, legs, as well as by the absence in the pro-male of the postero-lateral 

 emarginations and the deep marginal grooves near them. 



First and second stage nymphs measure 1.8 x 1.14 and 2.2 x 1.35, respec- 



