motes of tbe 



tling. I once found the trunk of a tree that had 

 been prone for half a century, and it was not only 

 all aglow, when the night was dark, but the out- 

 lines of a burrowing beetle and grubs could be 

 plainly seen. The glimmer had no impression on 

 the outside world. All was dark even at the very 

 edge of the wood. It was like looking in at a 

 window of an illuminated house. I saw this same 

 decaying tree-trunk many times afterward, but 

 there was no trace of phosphorescence. 



Very different are such local illuminings of the 

 solitary swamps from that sparkle and momentary 

 glow that we first see during the last week in May. 

 Here and there a single flash, and then darkness 

 deeper than before. As the weeks roll by, more 

 and more, until thousands of the light-bearing imps 

 are abroad, and the low-lying marshes fairly dazzle 

 with their efforts to replace the sun. Conditions 

 must be favorable for large gatherings of these in- 

 sects; but when they are collected in some limited 

 area, and no disturbing wind breaks their ranks, 

 the pyrotechnic display is simply marvelous. Com- 

 paratively few people, it would appear, have seen 

 the fire-flies at their best, although familiar with 

 them all their lives. They have seen a dozen or 

 more flash at once, it may be, and chased, when 

 children, single flies, to place under a tumbler, but 

 know nothing of secluded corners in brush-grown 

 meadows where a thousand are flashing together 

 and, by their united efforts, casting light over all 

 30 



