Bul. 597, U. S. Dept. of Agriculture. PLATE | 
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STAGES OF THE BOT FLIES, GASTROPHILUS. 
Upper left.—Gastrophilus haemorrhoidalis: Female, side view. Upper right.—G. haemorrhoidalis. 
arvee attached to margin of anus of horse. Left of center.—G@. haemorrhoidalis: Last-stage 
larva. Center.—G. intestinalis: Last-stage larva. Right of center.—G. nasalis: Last-stage 
Lower left.—G. intestinalis: Puparium, showing cap split off by fly inemergence. Lower 
larva. 
(Original.) 
right.—G. haemorrhoidalis: Male, side view. 
