Bul. 72, Bureau of Entomology, U. S. Dept. of Agriculture. PLATE IV. 
STIGMAL PLATES OF TICKS. 
Fig. 1.—Stigmal plates and anus of Dermacentor nitens, male. Fig. 2.—Stigmal plate of same. 
Fig. 3.—Stigmal plate of Amblyomma cajennense, male. Fig.4.—Same.female. Fig. 5.—Stig- 
mal plate of Dermacentor variabilis, female. Fig. 6.—Stigmal plate of Dermacentor occidentalis. 
Highly magnified. (Original.) 
