The Nest-building Odynerus 



on either side consist of Httle pimples, each 

 shaped like a truncated cone with a minute 

 opening at the top. One of these cones 

 rises on the right and left of each abdominal 

 segment, except the last two; there is also 

 one on the right and one on the left of the 

 metathorax and mesothorax. These two 

 are larger than the others. There are nine 

 pairs of perforated pimples In all. 



If we tease the creature, we sec welling 

 up from the bottom of these several little 

 craters an opalescent liquid, which runs and 

 spreads all over the larva. It has a strong 

 smell of bitter almonds, or rather of nitro- 

 benzene, commonly known as essence of 

 mirbane, a powerful and most repulsive 

 smell. The discharge of this substance is 

 a means of defence. We have only to 

 tickle the insect with a straw or to grip one 

 of its legs with the tweezers and the 

 eighteen scent-bottles at once begin to work. 

 Whoso handles the grub will find his fingers 

 stink and will throw away the noisome 

 perfumer In disgust. If the Chrysomela- 

 larva's object in placing nine pairs of nitro- 

 benzene-stills on its back was to repel man, 

 it has, I admit, thoroughly succeeded. 



But man is the least of its enemies. Far 

 more formidable is the Odynerus, who 

 193 



