514 IIKMI1TEKA. 



In the remaining suborders, the metamorphosis is, with the 

 exception of most of the Neuroptera, generally " incomplete," 

 the active larva and pupa closely resembling the adult, and 

 often scarcely distinguishable from it except in being wiiiirle. 

 This similarity of the adult condition to the larval and pupal 

 forms, as well as the equality in size of the different segments 

 of the body, the aquatic habits of many of the species, and 

 the numerous genuine parasites found among them, are indica- 

 tive of their low rank. 



HEMIPTERA. 



THIS order, including the true " bugs," the plant-lice, bed- 

 bug and body-lice, may be briefly characterized by the beak- 

 like sucking mouth-parts, composed of the mandibles and 

 maxillae, which are ensheathed by the large expanded labium, 

 while the labrum is small and short ; by the free, large protho- 

 rax, the usually angular short body, and the irregularly veined 

 wings, the veins being but few in number, while the fore wings 

 are often half coriaceous and opake. The metamorphosis is 

 incomplete. There arc many wingless parasitic forms, and 

 many aquatic species. 



The triangular head is nearly always sunken into the pro- 

 thorax, and is small in proportion to the rest of the body ; the 

 eyes are small, nearly globular and veiy prominent, and 

 the three ocelli are set far back, while the short, bristle-like, or 

 filiform antennae, with from five to thirteen or more joints, are 

 inserted below and far in advance of the eyes, so that the front 

 is broad and flat. The parts of the mouth form a four-jointed 

 solid hard beak. The mandibles and maxillre are lonir and 

 style-like, the latter without palpi ; they are ensheathed at 

 their base by the canaliculate labium, which has obsolete 

 palpi, while the lingua is short, but slightly developed, its 

 function of tasting the food, owing to the peculiar habits of 

 the suborder, being thrown into disuse. The lalirum is well 

 developed, being generally acutely triangular. The thorax is 

 constructed on the coleopterous type, the prothorax being 

 broad above, and the wings, when folded, concealing the rest 



