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deposit theii- eggs in the body of living insects, which, when hatched, 

 generally destroy their hosts to sustain their own life, and the gall-flies, 

 each of which forms a characteristic gall on its own special tree, are well 

 worthy of your notice. The horn-tails and saw-flies, destructive foes to 

 some of our most valuable trees, will be brought to your notice during 

 the present course of soirees. 



It is remarkable that the order Lepidoptera has not possessed more 

 followers, the gay colours of the butterfly are generally the first attrac- 

 tion of the young naturalist, and all clubs might be expected to have 

 many meml)ers working in this branch. Those who are so occupied 

 should make it their primary duty to prepare a list of our species. 



The order Di))tera, comprising flies, is large and important and 

 presents many suitable fields for beginners. 



The order Coleoptera, comprising beetles, you are familiar with. 

 All our Transactions contain papers on them, and a very valuable list 

 was issued in our last number. In the order Hemiptera, or bugs, we 

 want systematic workers. They occur everywhere^, in water and on 

 land, some are fouud only in the toi) branches of trees, some only in 

 the lower, while other forms remain stationary all their days. Any 

 one possessing house plants may follow this study most I'eadily ; here 

 we meet with the plant lice, which are so sought for by the ants and 

 carefully tended for the sake of tlieir honey-like secretion. Then there 

 are the grasshopper.^, locusts and crickets that should be descril)ed, 

 eack foiming a good subject for those by whom limited collections only 

 can be made, as also the dragon-flies, and allied insects. 



The class of Mijriapoda or centipedes is not so numerous as the 

 insects, nor as attractive, but should receive your attention as they are 

 wholly unstudied here. 



The class ArachniJa offers you the mites and spiders. The former 

 have received some attention and several new species are figured in our 

 publications. The spiders are repulsive olijects, l)ut most interesting in 

 their habits and modes of living. The wel)S furnish a study of them- 

 selves, I'anging from special forms, like the diving-bell of the water- 

 spider, to the common geometric web so well known to all. 



The Crustacea are the lower division of the arthropods, forming 

 to the waters of the world what the insects are to the laud. Nino- 



