WiREWORMS. 



89 



—Caudal segment of 

 the wireworm of 

 Melan otus cora- 



ls 



fields, ill oar State; Professor Forbes found an allied species 

 {M. crihulosus) nnicli more common in Illinois corn 

 fields. The insect is widely distributed, ranging at least 

 ^ from Nebraska to New Jersey and Canada. 

 Its life-history . — The mature wire- 

 worms vary in length from 25 mm. to 30 

 mm. They are of a light brown 

 color, with the head, thorax and last 

 segment considerably darker. (They 

 are described in detail in Bulletin 33, p 

 265). Figure 25 shows the character- 

 istics of the caudal segment of this =5 

 wireworm, and figure 26 (although it is of njunis, greatly en- 

 the closely allied species M. crihulosus) jfe?)^*^ ^* ^^^ 

 will serve equally well to show the principal features of 

 the whole worm. 



The insect spends at least three years as a wireworm ; 

 one specimen lived in our cages for nearly two 

 years. The change to a pupa takes place in earthen 



wfr'lwonn cells during July. The pupa is white and tender, and 



cwbtio"susK changes to a beetle in about 



enlarged 4* ., rni • • i 



diameters a moutli. Ihc pnucipal 



ftif tpr For* 



t)es). characteristics of the slend- 



er, glossy, dark brown beetle are well 

 shown in figure 27. They remain in 

 earthen cells in the soil all winter, 

 emerging in May. The secret of the 

 rest of their life remains with na- 

 ture. 



4. Drasterias elegans, Fabr. 



This species of wireworm is widely 

 distributed over the country, and has 

 been reported as exceedingly abundant ^■-J^^^^fS'^'^^.^l^.tl^i Ser 

 and injurious to young wheat in Forbes). 

 Indiana. We have found it quite abundant in sod land here. 



/^s Z^/6-A^5z;or?/.— Notwithstanding its abundance, comparatively 

 little is known of the life of this insect. It is one of the smallest of 



26 





