354 



THE SCOTTISH NATURALIST 



minor: thin-barked places well up the stem had been chosen. 

 In some cases the mother gallery had almost encircled the 

 stem, and when several such galleries are near one another 

 it will readily be understood that the conveyance of food 

 material is hindered. 



Fig. 5. — Galleries of M, minor and M. pmiperda on stem of Scots Pine. 



a = mother gallery M. minor. 

 a,= mother gallery M. piniperda. 

 h = larval gallery M. minor. 

 b,= larval gallery M. piniperda. 

 c = entrance to pupal bed M. minor. 



c,= pupal bed M. piniperda. 



d = entrance hole of parent beetle M. 



minor. 

 d,= entrance hole of parent beetle M. 



piniperda. 



The mother galleries of M. minor vary somewhat in 

 length ; in the example from which the figure was drawn, 

 the length was about 6 inches. When the larvae of M. minor 

 are full grown, they bore into the wood at right angles 

 to the length of the stem and then excavate a pupal bed 

 in the vertical direction. The fact that the full-grown larvae 



