30 BULLETIN 1369, U. 8. DEPARTMENT OF AGRICULTURE 
FIFTH STAGE 
The fifth or last larval stage of H. lineatun (fig. 16, a—c) tapers considerably 
toward the anterior extremity from about the eighth segment. The size of the 
larva varies from about 16 to 26 millimeters in length and from 7 to 11 milli- 
meters in width. The surface is more rugged than in the preceding stages, 
especially on the sides. The spinous armature is heavy; and, although varying 
greatly with different specimens on the dorsal and lateral sides, it is constant 
Fic. 11.—Second-stage larva of Hypoderma lineatum in submucous tissues of gullet. 
Enlarged 
ventrally on the posterior borders of segments 2 to 10, inclusive, and presents 
an excellent distinguishing characteristic for this species. The posterior stig- 
mal plates are somewhat kidney shaped, flat, or slightly excavated toward the 
pseudostigmatie orifice, and have radiating furrows which are very distinct in 
the younger specimens (figs. 16, d; 17). 
