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American Midland Naturalist Monograph No. 1 



the shape of an inverted Y with the mouth parts within the arms and the stem 

 extending to the anterior margin. 



Camerostome. — Distinct. 



Cheeks . — Absent. 



Capitulum. — Capitulum distant from the anterior margin. Basis capituli 

 subquadrate, slightly narrower anteriorly. Surface irregular, wrinkled and with 

 an elongated depression on each side parallel with the lateral 'border. With a 



100 200 3Q 



Fig. 22. Distribution of Ornithodoros nicollci Mooser and O. cooleyi Mclvor. 



