L':'.l 



iiiiitcly Iwciily-two iikimMis old. it chooses n siiit;iliic spol on tlic sm-f.-Ki- of 

 llio i,'rouii(l :ni(l huilils ;i l:illicc work of soft c.-nili ovit il-clf in lin- sli;i|i«' of 

 M small (Ionic, liy wliicli means it conceals itself in aiimit a ilay. In the con 

 structioii of tliis cell the larva removes earlli fmni iniderncatli itself liy 

 means of its mandihlcs. This it masticates in its nioutli for a slwut time, 

 after which it rofiurfjitates it in the form of a short ribbon like mass, 

 which it applies to tlie walls (»f the chamber. 



Almost as soon as this chamber is comi>lele(l the larva becomes sluKnish 

 and transforms to a pnpa. The extent of the pupal period was fomid to vary 

 from sixteen to eitrhreen days, at the end of which time the impae trans- 

 formed to adults and emerged. 



So far as the economic imi)ortance of lireflies is concerned it is j;enerally 

 bcli(>ved that they are of little or no importance. This conception is far 

 from correct. It is true that the adults are of little value as most of them 

 probably eat comparatively little, and most of the insects ui»on which they 

 feed are not injurious. The larvae, on the other hand, are voracious little 

 creatures which feed lariiely upon in.jurions species of animals, such as 

 cutworm larvae, sIuks. snails, etc Most of the soft bodied animals liv- 

 ing.' on the ground are injurious (unless it is the earthworm), and as the 

 food of firefly larvae is probably limited to these small animals, they nec- 

 essarily do much economic good in killing them. The slugs and cutworm 

 larvae are among our worst economic pests, and it seems evident that they 

 furnish a large part of the food of these larvae. ^Nlost of our fireflies live 

 two years as larvae, lience the numbi-r of larvae that are feeding on the 

 ground during any season is approximately twice that of the adult fireflies. 

 Any one who has been out during a June or July evening, knows that the 

 fireflies are one of our most abundant insects, which together with the vorac- 

 ious habits of the larvae leads one to the belief that they are of much 

 more economic importance than has been attributed to them heretofore. 



