210 PROCEEDINGS OF THE NATIONAL MUSEUM VOL. 10« 



were collected from the squirrel, Tamiasciwus hudsonicus rich- 

 ardsoni, at Florence, Ravalli County, Mont. Chiggers of this type 

 have been collected subsequently from Tamiasciwrns sp. in Ravalli 

 County. All have had five or more prongs on the palpal claw. The 

 evidence now available indicates that E. scmricola and E. ameri- 

 cana are the same species. In Wharton, Jenkins, et al. (1951), 

 the two species are listed as being synonymous. E. americana is 

 here considered to be a synonym of E. sciuricola. 



The single specimen on the slide in the series of cotypes marked 

 "C. E. F. X." is here designated lectotype. 



25. Euschongastia sp. 



Figure S,a; Plates 8, 20 



Description: Size: Length, 270 to 700 ; width, 225 to 505. 



Shape : Ovoid to broad ovoid ; broad oval. 



Gnathosoma: Setae generally like those of E. sciuricola. 

 Lateral seta on palpal tibia nude. Number of prongs on the palpal 

 claw variable in the five specimens and on the two claws of three 

 specimens; the distribution of prongs on the palpal claws of the 

 five specimens are as follows : Three and three prongs, three and 

 four prongs, three and five prongs, four and four prongs, and 

 four and five prongs. Dorsal tooth on the cheliceral blade farther 

 from the tip of the blade than in E. sciuricola. Punctae as in E. 

 sciuricola. 



Legs: Characters generally as for E. sciuricola. 



Scutum: Characters generally as for E. sciuncola. Posterior 

 margin tends to be more convex; lateral margins tend to be less 

 concave. Setae tend to be heavier. Sensillae rounded at tips. 



Summary of standard data of five specimens from Ravalli 

 County, Mont. (AM's and S's for four specimens) : 



AW 62-72, mean 67.8; PW 91-99, mean 96; AP 17-24, mean 20.8; 

 SB 23-29, mean 26.6; ASB 25-31, mean 27.4; PSB 8-15, mean 12.4; 

 AL 43-50, mean 47.2; AM 32-41, mean 37; PL 70-76, mean 71.2; 

 S 25-28, mean 25.8, Width of head of sensilla in four specimens, 

 all 17. 



Eyes: Two pairs; anterior pair lateral to the posterolateral 

 setae. Diameters of anterior eyes of three specimens, 12 to 13, 

 mean 12.7; of posterior eyes, 11 to 14, mean 12.3. 



Dorsal setae : Generally similar in form to those of E. setosa. 

 Somewhat heavier than those of E. sciuricola and more numerous. 

 Length of humerals of five specimens, 67 to 72 ; of setae near the 

 middle of the first posthumeral row, 50 to 57; of setae in the 

 posterior group, 42 to 48. 



