112 THE PINE DESTROYER. 



wood. (3) The second pair of jaws comes next. These are 

 known as the maxillse, and are far less formidable than their 

 predecessors ; horny, short, and blunt. Externally they are 

 pilose or hairy, but internally they bear a number of spinous 

 bristles. To the maxillae (4) is attached a pair of feelers or 

 palpi, which are known as maxillary palpi, to distinguish them 

 from the labial palpi (5), which are attached to the labium. In 

 each case the palpi are three-jointed, short, and somewhat blunt. 

 The chin (6) or mentum, which forms the lower part of the 

 mouth, is obovate, hairy, and bears a minute, ciliated lip, together 

 with the feelers or labial palpi. Behind, and on either side of the 

 antennae, are the small, elongated, compound eyes. The head, 

 though somewhat globular, is slightly produced, or sharpened 

 down in front, and (with the exception of the under surface) the 

 whole is covered with short hairs and minute punctures. 



Following the head is the thorax, which is minutely punctured, 

 and bears the fore pair of legs. These consist of the usual 

 parts — coxa (hip), trochanter, femur (thigh), tibia (shank), and 

 tarsus. The tarsus, as we have seen, is of importance in the study 

 of beetles, as its structure forms the basis of classification. 



Next comes the abdomen, which is cylindrical in shape, 

 and bears the middle and hind legs, the sheaths or elytra, 

 and the membranous wings. By turning the insect on its back 

 one is able to count the segments of which the abdomen is 

 composed. The wings, when not in use, are carefully folded under 

 their cases, but extended beyond them when opened for flight. 

 The elytra make the hinder portion of the insect slightly broader 

 than the anterior portion, but the symmetry of the entire insect is 

 well sustained. It will be seen that the wing cases have nine rows 

 of papillae each, from which hairs are produced ; while other hairs 

 grow irregularly between them, on both the outside and the inside. 

 Into the structure of the nervous system, the organs of generation, 

 and other details, it is not my purpose here to enter. 



Explanation of Plate IX. 

 Fig. 1.— Dead twig, showing excavations {n). 



3 J 



2. — Diagrammatic section. 



3. — Hyliu'yus pinijjerdu, eularged (5 diam.). 



4. — Antenna. 

 ,, 5. — Mouth ])arts. \ -yj ■.. ^ 



„ 6. -Wing-shield (elytron). ^ Mairuihed. 



,} 7. — Leg in different positions. 



n 



