MINNESOTA lUIJ. I'.L'G.S. 155 



Egg Stage. 



About the middle of June, ego-layini^- Ijegins and lasts until the 

 latter part of August. From all observations made, eggs of .V. 

 z'ciiatiis are never deposited in stalks of corn, not even under 

 artificial conditions where corn only was supplied. It was not until 

 August that eggs were actually found in the field, although eggs 

 were obtained in the insectary as early as June 16. The eggs were 

 always laid lengthwise, inside of and generally beneath a sheath of 

 Cy penis esculent us and were found to be from two inches below 

 the soil surface to three inches above the level of the soil. The 

 majority of the eggs, however, were deposited about one inch above 

 the surface of the soil. The actual act of placing an egg has not 

 been observed, but after it is deposited, it is found to be between 

 the two surfaces of a leaf sheath. Most of the eggs were held 

 between two parallel vascul;<r bundles, enough of the softer material 

 being eaten away on each side to allow the egg to fit into place. In 

 a few cases, one or both of these strands or Aascular bundles were 

 broken ; however, the eggs seemed to remain in place. Oftentimes, 

 one to three eggs were found in a single stem. The presence of 

 the eggs is indicated by a dark brownish stain at the point of the 

 injury on the sheath, this stain often being noticeal)le on two to 

 three sheaths on each side of the puncture. 



Eggs were obtained in the insectary on the following dates: 

 [une 16, 23, 24, 27, 29, and July 1 and 8. The incubation period 

 was determined to be 3, 4, 5, 10, 12, 14, 15, 17, 19, 20. 21, 22, and 

 34 days, respectively, or an average of 17.18 days. 



Larval Stage. 



When the larva is first hatched, the head as well as the 1)ody 

 is somewhat translucent in color, but after a couple of hours, the 

 head begins to turn brown. The first larval stage is somewhat 

 convex dorsally, especially anteriorly, head brownish, mandibles 

 dark brown, folds of trunk intricate and hairs scarce ; f< uir long anal 

 hairs, very distinctive, but difficult to see. 



The larva does not burrow up the stem more than three or 

 four times its own length. In no case have I ever found a single 

 larva inside of or feeding upon the bulbous roots of Cypcnis escu- 

 lent us, although in the insectary they were fed upon the bulbs 

 exclusively. The exact number of molts is not known ; however, it 



