194S] 
Wharton — New Peruvian Chiggers 
91 
Scutum: Roughly rectangular with punctate ornamenta- 
tion. A definite V-shaped ridge anterior to the pseudo- 
stigmata. Posterior lateral setae on lateral projections 
of the scutum. Scutal setae stout and feathered. Sen- 
sitise globose with fine setules over entire surface except 
on basal portion of stem. The Standard Data (Wharton 
1946) follow: 
Specimen 
AW 
PW 
SB 
ASB 
PSB 
AP 
AM 
AL 
PL 
S 
540-1 
79 
105 
20 
30 
21 
43 
55 
69 
75 
32 
621-6 
69 
99 
19 
31 
23 
35 
55 
62 
62 
23 
621-8 Tvpe 
76 
90 
21 
28 
18 
32 
50 
62 
54 
37 
621-9 
66 
88 
20 
27 
14 
27 
46 
62 
62 
27 
621-10 
69 
88 
18 
29 
20 
29 
44 
60 
62 
Mean 
72 
94 
19 
29 
19 
33 
50 
63 
63 
30 
Setce: Dorsal setae feathered about 55 microns long and 
arranged in indistinct rows, about 100 setae in all. Hu- 
meral setae not distinctly set off from other dorsal setae. 
Sternal setae feathered, 2 pairs between coxae I and II, 
about 40 microns long. Approximately 60 ventral setae 
arranged in indistinct rows from between coxae III to the 
posterior end, feathered, and about 50 microns long. 
Material: The following specimens all collected by O. P. 
Pearson at Caccachara, 50 miles S. W. of Have, Peru were 
studied : 
O. P. Pearson’s ff Host 
540 Pliyllotis 
darwini 
547 Cliinchillula 
sahamce 
621 Pliyllotis 
darwini 
Bate 
5 October 
1946 
7 October 
1946 
22 October 
1946 
Number of Specimens 
2 
1 
13 + Type 
(MCZ No. 3026) 
Diagnosis : Euschongastia pliylloti can be readily re- 
cognized in that it differs from other members of the 
genus as here interpreted in having the ventral seta 
extend anteriorly between coxas III. 
Be marks: Ewing restricted the genus Euschongastia 
to species with more than three prongs on the palpal claw, 
and erected the genus Ascoschongastia to include similar 
specimens with two or three prongs on the palpal claw. 
The type species of Ascoschongastia however has only 
