PTINID/E. 239 



Family XL.— PTINID^E, Leach. 



Antenna sometimes ten-jointed; filiform, elongate, simple or pectinated, occa- 

 sionally serrated ; or short, slightly thickened at the apex, with the three ter- 

 minal joints suddenly elongated: mandibles short, stout, hifid or bidentate at 

 the tip: palpi short, nearly equal ; the terminal joint rather largest: maxillae 

 bilobed : labium emarginate : head rounded, deeply immersed in the thorax, 

 •which is mostly cucullated: abdomen large, convex or gibbous: tarsi mostly 

 short, five-, rarely four-jointed. 



The Ptinidffi consist of two apparently distinct groups, one of 

 which has the antenna? filiform, with the tarsi simple and always 

 pentamerous ; the other having the three apical joints of the an- 

 tennae considerably and suddenly elongated, and slightly incras- 

 sated, with the tarsi occasionally tetramerous, and the penultimate 

 joint sometimes bilobed. 



The Ptinidse in many points of habit resemble the Dermestidee ; 

 like those insects they attack and devour, both in their larvse and 

 imago states, the dried remains of animals or wood : when touched, 

 they also counterfeit death, applying their antennas and legs closely 

 to the body, and withdrawing their head ; and so tenaciously fearful 

 are they, that they defy the utmost attempts to arouse them, the 

 united effects of fire and apparent torture not inducing them to 

 move a limb. 



The larvse, which subsist on dry wood, are white, soft, with the 

 head brown, scaly, and armed with two stout mandibles, with which 

 they tear the wood upon which they feed, reducing it to a fine 

 yellowish powder, with which their canals are filled, and in which 

 they change to pupse : — those that destroy animal remains resemble 

 closely the larvse of the lamellicornes; they are yellowish, pilose, 

 and velvety, elongate, cylindric, rugose, and curved posteriorly, so 

 that they have not the power of walking on a fiat surface; — they 

 change to pupa towards the end of summer in a cocoon formed of 

 the debris of the materials upon which they had previously sub- 

 sisted ; and the imago appears in the following autumn or spring: 

 the indigenous species are somewhat numerous, and require the 

 following subdivisions into genera. 



z 2 



