56 PROCEEDINGS ENTOMOLOGICAL SOCIETY 



dozen larvae to accomplish the feat. This presents an economic 

 side, as this beetle, when numerous, as it sometimes is in hard- 

 wood forests along the coast and along the border of streams, 

 is quite capable of doing considerable damage to timber. It 

 makes a broad gallery, extending deep into the wood, yet so 

 shallow as often to escape notice unless the beetle has emerged, 

 when a small round hole will be seen. 



Although species of these genera seemingly prefer lowlands 

 along waterways they are also found at considerable elevation, 

 infesting all fine-grained hard-woods. In these Mclasis pcctlni- 

 cornis and Thar ops sp. are often found closely associated and 

 with intermingling mines. They are also found closely asso- 

 ciated with a number of Cerambycid, Buprestid, and Ptinid 

 larvae, particularly a small Ptilimis sp. ; all seem to dwell 

 together in perfect harmony. One characteristic of this group 

 of borers in sound wood, and one which is rather unusual in 

 coleopterous larva?, is the fact that at no time can any trace 

 of ejected borings be found around the host plant. They seem 

 to work in complete secrecy, the borings being packed behind 

 the larva as it cuts its way through the wood, and the mine 

 always is wide enough for it to turn around. 



The larvae of this family are very sluggish in their move- 

 ments, and when taken from their mines seem incapable of 

 any movement beyond the bending of the body from side 

 to side. There is no record of any species of these beetles 

 having been observed in the act of ovipositing, but from 

 the appearance of the ovipositor it is probable that the eggs 

 are placed in the cracks and crevices of the bark, after the 

 manner of the Cerambycidae and Buprestidae, where they 

 hatch and the young larvae work their way directly into the 

 wood. They then mine through the sapwood and (unless the 

 tree is exceptionally large) into the heartwood, where they 

 attain their full development or nearly so ; they then work 

 their way into the sapwood again and excavate the pupal cell 

 from 0.25 to 1 inch from the surface, directly across the grain 

 of the wood. After completing its cell, the larva makes a small 

 round exit hole to within a hair's breadth of the surface for 

 the emergence of the young imago. While the larva is making 

 its pupal cell it is in a looped or doubled-up position, as some 

 species of the Buprestidae are often found, especially Agrilus. 

 It is doubtful whether the larvae are in this position at the time 

 of their pupation, as it would seem that the muscles of the body 

 should be straight at this time, or nearly so. There seems to 

 be no regular time for the general emergence of the images, 

 this period ranging from May to August inclusive, though 



