FOOT OF SYRPHUS. 99 



of Grammatophora and Pygidium of a flea being preferred 

 by many scientific observers. 



ELYTRON OF DIAMOND BEETLE. 



A most beautiful object, to be looked at with reflected 

 light that is as an opaque. These brilliant spots are groups 

 of scales, fashioned precisely like those of a butterfly's 

 wing, but owing to their iridescence, to the peculiar thinness 

 of the upper layer and the reflecting power of the secon- 

 dary layer, the colour changes like that on a soap-bubble 

 by the varied position of the light, the dark cell in which 

 the scales are set adding to their brilliancy. The Diamond 

 Beetle is one of the weevil tribe, and a native of South 

 America; but we have smaller Diamond Beetles in our 

 own country, and the Curculio of the oak and of the beech, 

 a little green and gold weevil, by no means rare on nettle- 

 plants, is quite as beautiful under the microscope, having 

 the same kind of scales, set in dark cup-like recesses on its 

 elytra. 



FEET AND LEGS OF INSECTS. 

 FOOT OF SYRPHUS. 



Although the feet are better studied with the leg and 

 upon the whole insect, yet, as those specimens are not so 

 easily obtained as the foot of Syrphus, it should by all 

 means form part of an educational box. 



The Syrphus is one of those flies which vibrate over our 

 flowers in the Summer, and haunt the Michaelmas Daisy 

 in the Autumn. They are called Drone-flies and Wasp- 

 flies, and are mistaken sometimes for one of the Hyme- 

 noptera. 



This foot displays that pair of membranous expansions 

 called pulvilli which enable the fly to walk up and down 

 smooth surfaces, on glass and on ceilings, in opposition to 

 the laws of gravity. They are fringed with minute hairs, 

 each of which is tubular, and secretes a viscid fluid which 

 attaches the foot to the surface of the glass or wall, and the 



