58 



Genus Ornithodoros 



the capitulum more or less visible dorsally in the replete adult. Integu- 

 ment thick, with hemispherical, brilliant contiguous granulations, larger 

 posteriorly. No obvious discs, but tracts where mammillae are absent, 

 arranged as in 0. savignyi. Numerous clubbed hairs between the 

 mammillae. No eyes. Venter: coxal and supra-coxal folds well 

 marked in unfed specimens; a pre-anal groove reaching to the supra- 

 coxal fold; a post-anal groove parallel to it, and midway between the 

 anus and the posterior border ; median post-anal groove reaching the 

 posterior border. Anus almost as wide as long, with numerous hairs ; 

 anal frame nearly quadrangular, 225 fi broad. Spiracles circular (180 

 to 200 (x wide), with crescentic perforate plate. Capitulum with integu- 

 ment finely honey-combed ; hypostome slightly lanceolate with a crown 



Fig. 85. 



Fig. 86. 



Figs. 85, 86. 0. turicata <j . L. 3'5 mm. Dorsum and venter. Specimen 

 from Guanajuato, Mexico. Original, N. and W. 



of numerous small teeth, followed by 2 | 2, 11 or 12 teeth per file ; two 

 hairs at the base of the hypostome ; digit (see Fig. 87); palps long and 

 only slightly tapering ; articles 1 and 2 equal in length (J 230 fi, 

 ? 300 ft) and articles 3 and 4 equal (</ 150 fj,, ? 170 /a); numerous 

 pennate hairs on dorsal surface of palps and basis capituli. Legs : coxae 

 contiguous, decreasing in size from I to IV ; bristling with very fine 

 spines, reinforced by granulations, especially on the posterior border; 

 tarsi cylindrical, slightly tapering at their tips; three dorsal humps, 

 more marked the more anterior the leg, scarcely visible on leg IV 

 (invisible in our specimen. See Fig. 58, p. 40); similar tubercles, 

 less salient, on the protarsi. 



