Smithsonian Report. 1951. Wigglesworth 



PLATE 2 



Figure 1. — Giant adult of Rhodnius re- 

 sulting from the metamorphosis of a 

 6th-stage larva, X 2. 



Figure 2. — Ist-stage Rhodnius joined by 

 neck to 5th-stage larva, causing dwarf 

 adult, X 3. 



Figure 3. — Giant or 6th-stage larva of 

 Rhodnius resulting from implantation 

 of the corpus allatum of a young larva 

 (secreting juvenile hormone). The site 

 of implantation appears as a scar on the 

 abdomen. X 2.5. 



Figure 4. — Rhodnius larva in 4th stage 

 decapitated 1 week after feeding and 

 connected by means of a capillary tube 

 with another 4th-stage larva decapi- 

 tated 24 hours after feeding. The 

 molting hormone from the first insect 

 causes the second to molt. X 3. 



