Objects for the Microscope. 135 



No better example can we have of the leg and foot of 

 the fly than this slide presents; for we see very distinctly 

 the coaa, or hip-joint ; the trochanter, a small joint by 

 which the thigh or femur fits into the coxa ; the tibia, 

 or shank-joint, which here is armed with two spines, and 

 the tarsi, or ankle-bones, as some think analogous to our 

 instep-bones, having two claws and pulvilli, or cushions, 

 set with glandular hairs. (See foot of fly in Scatophaga.) 

 Here observe the Leptis has three instead of two lobes. 



ASILUS. 



These are the most powerful and ferocious of the 

 Diptera, destroying Beetles and Ichneumon-flies, and may 

 be seen on the sunny side of woods, silently darting about, 

 or resting with a huge meal in their mouth, and then they 

 are pretty easily caught. They are bright, tawny-coloured 

 flies, very hairy ; the antennas erect and long, curved 

 upwards, and the proboscis standing forward. 



This is an example of relationship with Leptis as to the 

 wing-veins, and yet with a difference. You see the cubital 

 vein is forked, but simply so ; the discal areolet gives out 

 but two veinlets, and is joined to the cubital' by a short 

 transverse vein. The foot also observe two deep lobes 

 with a spine between them. Then look carefully at the 

 antennae, and compare them with those of Leptis ; you see 

 they are slender and styliform, and indicate an approach to 

 the tribe of Empis-flies, which, as they abound in our 

 gardens and may easily be procured, should have a place 

 in our object-box. 



EMPTS. 



(Snipe-fly.) 



Either the black Empis livida we see so often on our 

 laurels or flowers in the months of May or June ; or the 

 Empis stercorea, which swarms on the umbelliferous plants 

 by the wayside ; or the pretty little Hilara that plays over 

 the water-meadows or great ponds : any of these will give 

 a remarkable proboscis and a very pretty wing. 



