268 Genus Ixodes 



pherally, maroon centrally, placed in front of the posterior third of the 

 body-length ; hairs longer. Gapitulum (Fig. 269) 1 mm. long, dorsal base 

 broader than long, divided into three zones by lateral ridges which con- 

 verge in front; a median trapezoid zone almost completely occupied by the 

 contiguous porose areas ; two lateral triangular zones with salient angle. 

 (Digit 125 /j, long, resembling that of /. ricinus.) Hypostome lanceolate, 

 bearing 2 ] 2 files of 10-12 teeth, the marginal stout, pointed ; the internal 

 weak, blunt and separated from the median line, especially behind. 

 Palps of medium leugth, dilated at their internal border, especially 

 at the second article, which is longer than the third. Legs long, stout, 

 the two last articles of the fourth pair extending beyond the abdomen. 

 Coxae broad, brownish, hairy ; coxa I bears a flat spur at each of the 

 posterior angles; a similar spur at the postero-external angles of the 

 others. Tarsi long, tapering somewhat abruptly distally ; pad about as 

 long as the claws. 



A gorged female measures 5*5 x 3"2 mm. ; general colour maroon- 

 brown ; no marginal groove ; hairs whitish ; anus more anterior and 

 anal grooves longer than double the interval which separates them. 

 Four other $s measured 10 x 7 mm.; the greatest width at the posterior 

 third, the anterior part being narrow ; colour dark brown ; dorsum 

 glabrous, finely punctate, without characteristic depression. 



Nymph : Body oblong, narrowed in front, rounded behind, slightly 

 constricted on a level with the spiracles, may attain 4 - 5 x 2 mm., yellow 

 or reddish yellow all over. Scutum narrow, elongate, with borders but 

 slightly convex, posterior angle slightly ogival ; 0"67 x 0'46 mm., without 

 punctations; cervical grooves long, lateral grooves straight, parallel, 

 attaining the posterior border. Dorsum excavated by five longitudinal 

 grooves ; two anterior short, three posterior longer, and a median groove 

 prolonged further backward ; short, scattered hairs. Venter but slightly 

 concave ; sexual grooves widely separated in front, divergent backward ; 

 anus distant from the posterior border; anal grooves long, slightly 

 convergent behind ; hairs as on the dorsum. Spiracles small, rounded, 

 placed about midway along the body-length. Capitulum short (0'3 mm.), 

 conforms dorsally with that of $ . Legs similar to those of $ ; coxae 

 distant, with smaller spurs. 



Larva (hexapod) : similar to o, 1*9 x 08 mm. 



Neumann's description is based on two £ s and one £ from Didelphys 

 quica from Brazil, and two os from S. Brazil (Goeldi coll., now in 

 Neumann coll., Toulouse) ; two os and one larva found on Microdidelphys 

 sorex (?) from Rio Grande do Sul, Brazil (Brit. Mus.) ; five small </ s, 

 and four gorged % s from Buenos Ayres, Argentine (C. Berg coll.). 



