21 



Transformation to pupa takes place in a tolerably compact cocoon 

 formed in the earth and covered with grains of sand or dirt. Such as 

 have been seen were elongate, nearly reniform or bean-shaped, acutely 

 prolonged at each end, and measured, when divested of such parti- 

 cles of sand or dirt as did not adhere closely, from 12 to 14 mm. in 

 length and about 6 mm. in width. A cocoon is shown at f of. figure 3. 



LITERATURE. 



During the year 1881 this species was 

 the subject of some study on the part of 

 Dr. Howard, as also of Dr. W. S. Bar- 

 nard, at that time connected with this of- 

 fice. Among other things it was learned 

 that it had never been noticed in this 

 country prior to 1878 (Rept. Comm. Agr. 

 for 1881, pp. 142-145). Brief mention of 

 this stalk-borer as an enemy of corn has 

 been given by Prof. L. Brunei" in his re- 

 port to the State Board of Agriculture of 

 Nebraska for 1891 (p. 260), and this sums 

 up all that the writer is able to find that 

 bears in any wa}^ upon the biology of the 

 insect. A rather full bibliography is given 

 by Dr. Hulst (1. c). 



Figure 4 shows the nature of the work 

 of this stalk-borer in corn. 



NATURAE ENEMIES. 



Fig. 4.— Corn stalk showing work of 

 mailer corn stalk-borer — natural sizes 

 (after Riley, Rept. Dept. Agr., 1881) . 



Until the past year no natural enemies 

 of this species had been observed, to our 

 knowledge. From larvae received from Mr. Todd, Athens, Gra., a 

 hymenopterous parasitic larva issued October 15, and four da} r s later 

 was found to have transformed to a naked pupa, the adult issuing 

 early in November. It has been identified by Mr. Ashmead as Orgilus 

 {Microg aster) mellipes Say. 



REMEDIES. 



Previous observations have shown the practical impossibility of a 

 perfect remedy for this insect, since it has been observed to hibernate 

 in all three stages of larva, pupa, and adult. 



Only two remedies suggest themselves: The plowing up and burn- 

 ing of the corn stubble or other infested material as early as possible 

 after the crop is made, as already advised in the 1881 report, and rota- 

 tion with some crop not affected by the species. It seems probable 

 that this insect would not injure any of the smaller cereals, sweet 

 potatoes, cotton, melons and other cucurbits, potato, tobacco, and 



