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yellowish-brown as well as the legs, the mouth parts, however, are 

 dark brown. The mandibles are furnished with several teeth. The 

 thorax is dirty white. The abdomen is of a slate colour except the 

 first and last segments, which are, like the thorax, dirty white. The 

 dorsal vessel can be easily distinguished. It can be noticed that it 

 widens out eight times, showing the presence of eight chambers 

 connected by narrower tubes. 



A rather interesting peculiarity can be observed on the second 

 and third pairs of legs. The middle pair are longer than the 

 anterior legs, and near the base of each is a flat rugose surface 

 directed backwards and somewhat to the outside. The posterior 

 pair are very small (smaller than the first) and in each the side of 

 the penultimate segments directed towards the rugose surface is 

 toothed. The larva produces a distinct stridulation by rubbing the 

 teeth of the third pair against the rough surface on the second pair 

 of legs. The vibration is very noticeable when an adult larva, or 

 even the cell containing one, is held in the hand. This i-s quite 

 startling when first experienced, and one feels nearly the same 

 sensation as if one gets an electric current from a small coil through 

 the hand. For what these stridulations are used I could not tell, 

 but I suppose they serve as defence against enemies or strange 

 insects penetrating the mass. 



When the time for pupation arrives, the larva gets rid of all its 

 undigested food and uses it to plaster the walls surrounding itself. 

 The walls consist of unconsumed food and are at first in a very 

 rough state, but are made quite firm and smooth, and the cavity is 

 reduced in size to form the pupating cell. 



^Yhen the cell is prepared, the larva lies on its back and the 

 abdomen becomes shorter and much broader. It then awaits 

 pupation. The undigested food is kept all the way through and is 

 always used to plaster the final cell. When, however, the wall of 

 the cavity in which the larva is feeding becomes injured or broken, 

 the larva at once starts to repair this. Excreting some undigested 

 food, it puts this on the border of the hole, and, taking some 

 mouthfuls of food, mixes the whole up and thus obtains a rather 

 moist mass with which it gradually closes the hole. Soon the 

 moisture is absorbed by the other food and the new part becomes 

 fairly hard. 



When the pupa is just formed, it looks very pretty. It is then 

 quite white. The lateral borders and disc of pronotum, as well as 

 each abdominal segment, are covered with short brown bristles. 

 The abdominal segment is furnished with two fleshy organs, a few 

 mm. long, and directed laterally backwards. After remaining four 

 to five weeks in the pupal state the perfect insect emerges from the 

 pupal skin in September. A few days before the emergence of the 

 beetle, the head, disc of pronotum, legs, and last abdominal seg- 

 ment begin to darken and, some time later, the whole pronotum, as 

 well as the above-named parts, become almost black. The beetle, 



