LELUST RA RVON'S, 
PLATES, 
PuaTE I. Ticksand spotted fever in the Bitter Root Valley, Montana. Fig. 1.— 
View in Lo Lo Canyon, which leads into the Bitter Root Valley, 
showing conditions under which ticks thrive. Fig. 2.—Camp 
laboratory near Florence, Mont., in one of the most heavily in- 
fested ‘localities ‘known: 2 fi: i2h25 $32 2¢ 5522252305 eee eee 
II. The Rocky Mountain spotted-fever tick (Dermacentor venustus). 
Fig. 1.—Adult female unengorged, dorsal view. Fig. 2.—Adult 
male, dorsal view. Fig. 3.—Adult female unengorged, ventral 
_view. Fig. 4.—Adult male, ventral view. Fig. 5.—Adult female 
mr aC OF Gepoartneened. -- or 2. s fe ares Ie ester een cle eee 
III. Spotted-fever tick (Dermacentor venustus) and Dermacentor albipictus. 
Fig. 1.—Adult spotted-fever tick which has deposited eggs. Fig. 
2.—Larva of spotted-fever tick. Fig. 3—Engorged nymph of 
spotted-fever tick. Fig. 4—Same, ventral view. Fig. 5.—Adult 
male of Dermacentor albipictus. Fig. 6.—Adult female of Derma- 
centor albipithts, witerigerged: . 2. 22a vee fe Sie PIS 
TEXT FIGURES. 
Fic. 1. Map showing area in which the spotted-fever tick occurs....-...------- 
2. Diagram showing possible seasonal history of spotted-fever tick. - ..-.- 
3: Dippime “vate... 55. sol esag- seas ste n eae ae ce oi ee 
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