122 



CRASS AND INSECTS. 



FIG. 149. Seventeen-year cicada. 



FIG. 150. A portion of a grass- 

 stem, with the young froth-in- 

 sects (Ptyelus) magnified, a, 

 the insect reaching out the 

 hinder part of the body to se- 

 cure a bubble of air ; b, an in- 

 sect allowing a bubble of air 

 to escape in the fluid the dot- 

 ted line b indicates the bub- 

 ble ; c, the mouth-parts, like a 

 sting, piercing the grass. (Af- 

 ter Morse.) 



bering 400 or 500, are depos- 

 ited the last of May in holes 

 in the twigs of the oak, so 

 formed by the ovipositor that 

 the wood covers them. They 

 hatch in about six weeks, the 

 larvae burrowing in the ground 

 and remaining nearly seven- 

 teen years, then appearing in 

 the adult form. Allied to them 

 are the lantern -flies {Fulgo- 

 ridcz}* 



Leaf-Hoppers (Cercopi- 

 dcz). The tree- or leaf-hop- 

 pers are remarkable for their 

 strange shapes. They are 

 small, with broad, triangular 

 heads, and hind-legs adapted 

 for leaping. The froth-insect 



* The following authors have ex- 

 pressed their belief from observation 

 and other sources in the phosphores- 

 cent properties of the Fulgotida : 

 Madame Merian, Dr. Donovan, au- 

 thor of " Insects of India," Marquis 

 Spinola, a colleague of Mr. West- 

 mael, Lady Seymour, and Dr. Phip- 

 son. 



