502 AN INTRODUCTION TO ENTOMOLOGV 



insect varies greatly in size, some individuals being not more than 

 half as large as others. 



The larvas live in decaying wood, and are often found in the 

 trunks of old apple trees. It was formerly believed that they fed on 

 the decaying wood; but they have been found to be carnivorous. 

 The larger larvas are about 60 mm. in length. 



There is an elater quite similar to the preceding that differs in 

 having the eye-like spots less distinctly marked; this is Alaus myops. 

 This species is not as common as the preceding one. 



The family EUCNEMID^E was formerly regarded as a subfamily 

 of the Elaterid^. It differs from the Elateridae, as now restricted, 

 in having the labrum concealed, and in that the antennas are some- 

 what distant from the eyes, and their insertion narrowing the front. 

 The adults are found under bark or on the leaves of plants ; most of 

 the species are rare. "The larvee have a striking resemblance to those 

 of the family Buprestidae, both in form and habits, being abruptly 

 enlarged in front, and usually occurring in wood which has just begun 

 to decav." (Blatchley '10.) 



The' family THROvSCID^ includes a few small species which 

 resemble the elaters and buprestids in having the prosternum pro- 

 longed behind into a process, which is received in the mesostemimi. 

 They differ from the elaters in having the pro thorax firmly joined to 

 the mesothorax, and the front coxal cavities closed behind by the meso- 

 sternimi instead of by the prosternum; and from the buprestids in 

 having the ventral abdominal segments all free. The adult beetles 

 are found on flowers. 



Family BUPRESTIDS 

 The Metallic Wood-Borers or Buprestids 



The buprestids resemble the click-beetles somewhat in form, being 

 rather long and narrow; but they are easily recognized by their 

 metallic coloring. Their bodies are hard and inflexible, and usually 

 appear as if made of bronze ; but some species exhibit the brightest 

 of metallic colors. The antennse are serrate; the first and second 

 abdominal segments are grown together on the ventral side ; and these 

 beetles do not have the power of springing when placed on the back. 



The adults are found upon flowers and upon the bark of trees, 

 basking in the hot sunshine. Some of them fly very rapidly, with a 

 loud buzzing noise; and some drop to the ground when disturbed, 

 and feign death. 



Most of the larvae are borers, feeding beneath bark or within 

 solid wood. In such species the body is of a very characteristic 

 form, which is commonly designated as "flat -headed."' The flattened 

 portion, however, is composed largely of the segments immediately 

 following the head. The first thoracic segment is very wide and flat; 

 the next two or three segments are also flattened, but are successively 

 smaller; while the rest of the body is quite narrow and cylindrical. 



