21 



and gently rubbed over with a clean cloth;, until 

 it is quite smooth. 



The following mode of arrangment is that 

 adopted by London entomologists, and is cer- 

 tainly the best calculated for displaying the 

 affinities of a series of insects. Double pencil 

 line are ruled to form columns, according to the 

 width of the insects, which are to be placed be- 

 tween them. The larger species of Coleoptera, 

 Orthoptera and Hemiptera are arranged side by 

 side in pairs, and the smaller species in a greater 

 number according to their size, having an open 

 winged specimen below them. Hymenoptera, 

 Trichoptera, Lepidoptera, and Diptera, are ar- 

 ranged singly, placing the males first : the sexes 

 are always procured if possible. Of the but- 

 terjlies four specimens are retained ; a male and 

 female showing the upper side of the wings, and 

 one of each showing the underside. Of the moths, 

 only the upper side is exhibited. Varieties are pre- 

 served as far as possible, as they are often of 

 great use in determining species. The generic 

 name is always stuck by a pin at the head of a 



