362 



Forty-sixth Report on the State Museum 



Three of the larva^ of the cucumber beetle were boring into the 

 stalk at about an inch downward upon it, and several round holes were 

 seen that had been made by others — some of them 

 clean cut and others surrounded with irregular 

 erosions; still others were superficial and had not 

 extended into the root. On cutting open the stalk 

 seven nearly full-grown larva? were taken from its 

 interior, within a length of two inches, in longitu- 

 dinal tunnels which they had excavated. Figure 30 

 shows the opei-ations of the larvte within a root, 

 and Figure 31 the larva in natural size and enlarged. 

 The best method of protection from this form of 

 attack woiild undoubtedly be in preventing the 

 deposit of the eggs on the stalk of the plants by 

 the parent beetle, by covering them during the 

 early stage of growth with a thin loose muslin 

 or netting. By the time that they have out-grown 

 such a protection, they will have attained a sufficient 

 size and vigor of growth to enable them to resist 

 attack unless it be unusually severe. Possibly an 

 Fig. 30.— Cucumber rootgjjj.|„ application of the burdock infusion which is 



infested with the larva? ■ i • i t-t 7 n t t- » h^ 



of the striped cucumber noticed in the r ifth liepoH on the Insects of JSeio 

 beetle. (After Fitch.) York, page 158, if repeated at intervals of about a 

 Aveek, would prevent attack by rendering the plants distasteful to the 

 newly hatched larvte. Kerosene emulsion — one-iifteenth kerosene,. 

 « mmjx w > poured about the roots would destroy 



the eggs already deposited and such 

 of the larviB as had not already bur- 

 rowed into the root beyond its reach. 

 Fig. 31 -Larva of the striped cucumber I^ a communication recently made^ 

 beetle, diabrotra vittata, natural size by me to the Country Gentleman 



andenla-ged. (After Fitch.) . . -, 13 r ^\r i ;i 



experiments by Proiessor W eed and; 

 others, with remedies and preventives for the beetle were noticed as 

 follows: 



A correspondent asks, what is the best remedy and how should it be 

 applied for the destruction of the striped cucutnber beetle? 



This question is often asked, but can not be replied to satisfactorily. 

 Various ^preventives are announced from time to time, as invariably 

 giving efficient protection, but when tried by other persons, in different 

 localities, only partial success is reported. 



Last year a series of careful experiments were made by Prof. Weed,, 

 of the Ohio Agricultural Experiment Station in order to test the value 



