THE LOCUST OF THE NORTH-WEST. 



387 



blades instead of two. When one of these insects is about 

 to lay her eggs, she drives these little wedges into the 

 earth ; these being opened and withdrawn, enlarge the 

 orifice, upon which the insect inserts them again, and 

 drives them down deeper than before, and repeats the 

 operation above described, until she has formed a perfora- 

 tion large and deep enough to admit nearly the whole of 

 her abdomen." 



The locust of the north-west (Acrydiiim femiir-riibrum) 

 has been long noticed in the United States, and particu- 

 larly in New England. In the State of Maine they ap- 

 peared in such numbers during the years 1743, 1749, 

 1754, and 1756 that days of fasting and prayer were 

 appointed on account of the threatened calamity.* In 

 Massachusetts and Vermont they showed themselves in 

 1797 and 1798. In 1838 they appeared in the vicinity 

 of Baltimore in immense numbers. 



The following description is from the pen of Dr. 

 Harris : — 



Acrydium femur-rubrum — Bed-legged Locust. 

 Grizzled with dirty olive and brown ; a black spot 

 extending from the eyes along the sides of the thorax ; 

 an oblique yellow line on each side of the body beneath 

 the wings ; a row of dusky brown spots along the middle 

 of the wing covers, and the hindmost shanks and feet 

 blood red, with black spines. The wings are transparent, 

 with a very pale greenish-yellow tint, next to the body, 

 and are ruled with brown lines. The hindmost thighs 

 have two large spots on the upper side, and the extremity 

 black, but are red below, and yellow on the inside. The 

 appendages at the tip of the body in the male, are of a 

 long triangular form. Length from § to 1 inch, expanded 

 1\ to If inch. 



* Williamson's History of Maine, quoted by Dr. Harris. 



