252 MANUAL OF VEGETABLE-GARDEN INSECTS 



the mandibles are borne. The insect passes the winter usually 

 in the adult stage hidden away in dry sheltered places. The 

 adults appear in the spring and are often seen resting on the 

 stems and foliage of rhubarb and dock. They feed on the edge 

 of the leaves and puncture the stems with their beaks. The 

 female deposits her eggs singly in cavities about i inch deep 

 in the stalks of dock, sunflower, thistle and in the leaf-stems and 

 flower-stalks of rhubarb. The eggs are oblong oval, yellowish 

 white in color and about xe hich in length. They hatch in a 

 week or ten days when deposited in their wild food plants but, 

 as ])reviously stated, are not able to develop in rhubarb. On 

 hatching the larva burrows down through the stalk so that 



when it reaches maturity it occu- 

 pies a cavity just below the surface 

 of the ground. Although many 

 eggs are often laid in the same 

 stem, usually only one grub reaches 

 Fig. 151. — The rhubarb maturity. The full-grown larva is 



curculio(X2|). „ .-^ 1 u^ s • 1 • 



a footless grub about i inch m 

 length and is white with a brownish head. As the eggs are 

 laid over a considerable period from the first of June till the 

 middle of July, the grubs do not reach maturity at the same 

 time. The larval period occupies, on an average, eight or 

 nine weeks. In New Jersey the greater number are mature 

 by the middle of August. The pupa is white, about |^ inch 

 in length, and is found in a rather large cavity in the crown 

 of the plant just below the surface of the ground. The pupal 

 period occupies a little over a week. After transformation 

 the beetle remains in the pupal chamber for several days until 

 fully hardened and then gnaws its way out and after feeding a 

 short time goes into hibernation. There is only one generation 

 annually. 



The beetles are easily seen resting on the plants and may be 

 readily captured and destroyed by hand. All wild plants in 



