COLEOPTERA. 147 



tudinal stria at each posterior angle. The wing- 

 cases, or elytra, are longitudinally striated ; the wings, 

 which in most beetles are concealed beneath the elytra 

 when the insects are at rest, being absent. The tibiae 

 of the fore legs are notched on the inside (fig. .24 a), 

 a fringe of hairs being situated in the notch ; the 

 tarsi are 5 -jointed (fig. 245), the first four joints 

 being triangular, the last elongate and terminated 

 by two curved claws. In the male the three first 

 joints of the tarsi of the anterior legs (fig. 24 b) are 

 dilated and heart-shaped. 



The parts of the mouth (which are named after an 

 analogy with those of the higher animals) consist of 

 the following pieces : An upper lip, or Idbrum (fig. 

 25 0), which is squarish (quad'rate) and slightly 

 notched ; a quadrate lower lip, or Idbium (fig. 27), with 

 a process on each side, and two 4-jointed lip-feelers 

 or labial palpi (b) ; and below the labium is a chin, or 

 mentum (fig. 270), with a projecting bifid tooth: 

 these parts form the roof and the floor of the mouth. 

 Next come the man'dibles (fig. 26), one on each side, 

 which are stout, curved, and pointed ; beneath which 

 are the maxil'lce (fig. 28), also one on each side, and 

 provided with a fixed claw (a), ciliated on the in- 

 side, and furnished with two pairs of jaw- feelers, or 

 maxillary palpi, the inner (b) being 2-jointed, while 

 the outer (c) are 4-jointed. It will be noticed that 

 the jaws work laterally, or from side to side, and not 

 perpendicularly as in the higher animals. 



These parts may be found in most beetles which 

 the observer may submit to examination, being how- 

 ever somewhat modified in different genera. We 

 may consider those existing in the Lady-birds, or 

 species of Coccinetla, by way of comparison. The 

 body in these insects is very convex, and the head 

 sunk deeply in the thorax. The antennae (fig. 15) 

 are short, clubbed (clavate), and compressed. The 

 thorax is short and lunate, or half-moon shaped. 



o2 



