Pigmy Potato Beetle . 85 
this is due to the beetles or subsequent decay I could not say for 
certain, but I believe from the latter. 
On July 14th, I wrote to this effect to Mr. Staines, to which be 
replied that he had also come to the conclusion that these beetles 
were causing much harm. 
Not content with damaging potatoes, they spread into an onion 
B 
A 
Fig. 10. — the pigmy potato beetle (Bathyscia ivollastoni, Jans.) 
A, Section of damaged potato (c, holes eaten by the beetle, D) ; B, damaged 
outer surface. 
bed and ruined quite half the crop. Just as in the potato crop, so 
with the onion, they work underground. The rootlets of the onions 
were eaten off, so that the plants fell down ; the beetles also nibbled 
at the lower part of the onions and so caused them to split and become 
worthless. I tried them with numerous other food plants experi- 
mentally, and found parsnips the only one they would touch ; but if 
a parsnip, an onion, and a potato were put in the same box, they 
