INSECTS 



187 



carefully observed will prove to be of absorbing interest. 

 The author has often watched individuals of one kind (a 

 species of the genus Ainmophila) at work on the salt 

 marshes of San Francisco Bay near Stanford University. 

 These marshes (fig. 141) are nearly covered with a dense 

 growth of a low fleshy-leaved plant, but here and there 

 are small, perfectly bare, level sandy places, which shine 

 white and sparkling in the sun because of a thin incrusta- 



FlG. 145. — The quince curculio (a beetle), Conotrachelus cratcegi, natural 

 size and enlarged. (Photograph by M, V. Slingerland.) 



tion of salt. In September these bare places are taken pos- 

 session of by many female Ammophilas, which make short 

 vertical nest-burrows all over the ground. An Ammo- 

 phila having chosen a site for its nest bites out a small 

 circular piece of the salty crust, and with its strong jaws 

 digs out bit by bit a little well. Each pellet dug out is 

 carried by the wasp, flying a foot or two from the mouth 

 of the tunnel, and dropped. To emerge from the hole 



