8 INTRODUCTORY LETTER. 



like liquid drops, or plates of gold and silver a ; or with 

 scales or pile, which mimic the colour and emit the ray 

 of the same precious metals b . Some exhibit a rude ex- 

 terior, like stones in their native state c , while others re- 

 present their smooth and shining face after they have 

 been submitted to the tool of the polisher: others, again, 

 like so many pygmy Atlases bearing on their backs a 

 microcosm, by the rugged and various elevations and de- 

 pressions of their tuberculated crust, present to the eye 

 of the beholder no unapt imitation of the unequal surface 

 of the earth, now horrid with mis-shapen rocks, ridges, 

 and precipices — now swelling into hills and mountains, 

 and now sinking into valleys, glens, and caves d ; while 

 not a few are covered with branching spines, which fancy 

 may form into a forest of trees e . 



What numbers vie with the charming offspring of Flora 

 in various beauties ! some in the delicacy and variety of 

 their colours, colours not like those of flowers evanescent 

 and fugitive, but fixed and durable, surviving their sub- 

 ject, and adorning it as much after death as they did 

 when it was alive ; others, again, in the veining and tex- 

 ture of their wings ; and others in the rich cottony down 

 that clothes them. To such perfection, indeed, has na- 

 ture in them carried her mimetic art, that you would de- 

 clare, upon beholding some insects, that they had robbed 

 the trees of their leaves to form for themselves artificial 

 wings, so exactly do they resemble them in their form, 



a Hesperia Cupido, F. PapUio Passiftora:, Lathonia, L. &c. 

 b Pepsis fuscipennis, argentata, F. &c. 

 c The species of the genus Trox, F. 

 d Many of the Scarabceidce, Dynastida;, MacLeay, &c. 

 e Many caterpillars of Butterflies. Merian Surinam, t. xxii, xxv, 

 &c and of Sawflies. Reaiun. v. k xii. /. 7, 8—14. 



