44 THE ORTHOPTERA OF MINNESOTA. 



markings. The small and flattened head, (Fig. 16, 6 and c), is 

 dark brown, with broad, almost triangular jaws. All the 

 larva found during August and September, though varying 

 greatl}" in size, possess similar forms, and all are almost un- 

 able to move. They are most frequently close to the egg- 

 pods, which in some cases are found empty. The young 

 maggots must possess a very different form and decidedly 

 different habits from the adult larvae, otherwise they would 

 be altogether too slow and awkward to find the eggs of 

 locusts. No pupae have been found and all the larvae kept 

 in breeding cages have dried up before changing. 



BLISTER-BEETLES. 



Several species of Blister-beetles or Spanish-flies occur in 

 large numbers throughout the infested region. In fact some 

 of them cause considerable damage to potatoes and other 

 plants. Many of these blister-beetles are known to feed in 

 their early stages upon the eggs of locusts. A very interest- 

 ing report upon the peculiar life-histories of these beetles 

 was published in the "First Annual Report of the United 

 States Entomological Commission." The following species 

 of these beetles are abundant in Minnesota: the Ash-gray 

 Blister-beetle [Macrobasis unicolor Kirby), the Margined 

 Blister-beetle [Epicauta cinerea Forst.), the Black Blister- 

 beetle {Epicauta pennsylvanica De G.), and the Red-headed 

 Blister-beetle {Epicauta trichrus Pall.). All these beetles, 

 frequenth^ best known as being very injurious to potatoes, 

 beans and other cultivated plants, surely have one great re- 

 deeming character, in being our best friends by checking 

 an undue increase of noxious species of locusts. Their life- 

 history may be summed up in a few words : they deposit, 

 from Jul}^ to October, their orange or yellow-colored eggs in 

 irregular masses in loose ground, each female producing 

 from four hundred to five hundred eggs. In about ten days 

 these eggs hatch, producing very active, long-legged larvae 

 with large heads and strong jaws, which run about search- 



