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BULLETIN 1369, U. S. DEPAKTMENT OF AGRICULTURE 



FIFTH STAGE 



The fifth or last larval stage of U. Uneatum (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 



larva of Hypoderma Uneatum in submucous tissues of 

 Ii^nlarged 



ullet. 



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 

 pseudostigmatic orifice, and have radiating furrows which are very distinct in 

 the younger specimens (figs. 16, d; 17). 



