180 



INSECT ARCHITECTURE. 



summer and autimm, in sandy places, is long, cylindric, 



soft, wliitish, and fumislied with six scaly brown feet. 



The head is of a square form, with six or eight eyes, and 



very large in proportion to the body. They have strong 



A, The Gnib. 



Nest of the Grubs of Ephemera. 



5, Perforations in a river banl^. C, One laid open to show the 

 parallel structure. 



jaws, and on the eighth joint of the body there are two 

 fleshy tubercles, thickly clothed with reddish hairs, and 

 armed Avith a recurved horny spine, the whole giving to 

 the grub the form of the letter Z. 



Nests of Ephemera^ in holes of Cossus. 



With their jaws and feet they dig into the earth to the 

 depth of eighteen inches, forming a cylindrical cavity of 

 greater diameter than their body, and furnished with a 

 perpendicular entrance. In constructing this, the giub 



