6 BowDiTCH on Hydrocharis obtusatus and Magdalis olyra. 



The larva undergoes its transformation in the ground, in 

 the vicinity of the water, where it was hatched but T have 

 never seen its cocoon. 



I should judge from this experiment that the eggs took 

 about ten days to hatch, and the larvse about thirty days 

 to attain full size. I infer that the whole summer is passed 

 in the ground as pupa, the beetles probably emerging in 

 early spring. This early and quick arrival at maturity en- 

 ables them to breed in many temporary ponds which are 

 dry in summer though full in April and May. 



Grassy, leafy, shady spots are best for this species, the 

 eo-o* cases are often found floating; on the surface early in 

 May. 



Magdalis olyra Herbst. This is one of the true bark 

 eating Curculios and lives on the inner or sap bark only. In 

 early summer the beetles may be found walking on the 

 leaves of the hickory tree, or in the cracks and crevices on 

 the bark, boring holes with their snouts in which to deposit 

 their eggs. 



After the eggs are laid, and before the tree shows any 

 outward signs of failing, rfn experienced eye will detect their 

 presence, by a small, round spot of whitish borings, which 

 is left by the beetles when they make their ovipositing 

 hole. 



The eggs hatch and reach maturity by the close of the 

 summer. The larva is suiall, not over a quarter of an 

 inch long, yellowish white in color and slightly chunky tow- 

 ards the head which is darker than tae body, They tunnel 

 the bark in every direction leaving only just enough tissue 

 to prevent the bark warping away from the tree. 



When fully grown, that is, in autumn, the larva exca- 

 vates for itself a small, smooth, and pod-shaped hole in the 

 bark, in which it undergoes its changes, emerging from the 

 tree in spring. 



