Rambles with Nature Students 



Januar? 



' My heart is awed within me, when I think 



Of the great miracle that still goes on 



In silence round me the perpetual work 



Of Thy creation, finished, yet renewed 

 For ever. Written on Thy works, I read 



The lesson of Thine own eternity.' 



Bryant. 



PTEROMALUS 



JLTHOUGH the weather is very cold, 

 I see a quantity of little hardy flies 

 upon the window-pane. Apparently 

 they are unaffected by a temperature 

 which paralyses almost all other insects in the depth 

 of winter. 



This special little fly, Pteronialus> has a very curious 

 life-history ; for it lays its eggs in living caterpillars, 

 chrysalides, or hybcrnating bluebottle flies. The 

 eggs hatch into very minute grubs, which feed upon, 

 but do not kill, the unfortunate insect until they are 

 full grown, when they emerge from the creature they 

 have preyed upon, turn into tiny chrysalides, and 

 in due time appear as peifect flies. They are so 

 excessively small that they can creep through a mere 



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