136 THE STORY OF TOE EARTH AND MAN. 



forests, was that of the May-flies and shad-flies, or 

 ephemeras, which spend their earlier days under 

 water, feeding on vegetable matter, and afibrding food 

 to many fresh-water fishes — a use which they no 

 doubt served in the coal period also. Some of them 

 were giants in their way, being probably seven inches 

 in expanse of wing, and their larvaa must have been 

 choice morsels to the ganoid fishes, and would have 

 aflbrded abundant bait had there been anglers in 

 those days. Another group of insects was that of the 

 weevils, a family of beetles, whose grubs must have 

 found plenty of nuts and fruits to devour, without 

 attracting the wrathful attentions of any gardener or 

 orchardist. 



A curious and exceptional little group of creatures 

 in the present world is that of the galley-worms or 

 millipedes; wingless, many -jointed, and many-footed 

 crawlers, resembling worms, but more allied to 

 insects. These animals seem to have swarmed in the 

 coal forests, and perhaps attained their maximum 

 numbers and importance in this period, though they 

 still remain, a relic of an ancient comprehensive type. 

 I have myself found specimens referred by Mr. 

 Scudder, a most competent entomologist, to two 

 genera and five species, in a few decayed fossil stumps 

 in Nova Scotia, and several others have been dis- 

 covered in other parts of the world. It is not 

 wonderful that animals like these, feeding on decayed 

 vegetable matter, should have flourished in the 

 luxuriant Sigillaria swamps. A few species of scor- 



