102 THE ORDER OF COLEOPTERA. 



The Ptini iiroper subsist upon substances in a state of incipient decay, 

 and are often found in cellars and out-buildings. The Anohii are usually 

 found in wood more or less decayed; but the Bostrichi bore into solid 

 wood, and are often seriously injurious, more especially to forest trees. 

 Indeed, the last mentioned insects bear so striking a resemblance, both 

 in their short cylindrical forms and their eminently wood-boring habits, 

 to the short-horned wood-borers fScolytidccJ, in the tetramerous section, 

 that one feels strongly tempted to i^lace them in the latter tribe; but in 

 the details of their organization they are more closely allied to the more 

 highly organized Ptiuidne, especially in the more fully devek)ped anten- 

 na! club, labrum, and maxillary palpi. The larvae also have six feet, 

 whilst those of the Scolytidas are footless. 



The following are the principal genera: 



A. Antennae filiform, sometimes branclied. Tibial spurs very small or wanting ; tarsi distinctly 

 5-,jointe(l. 

 B. Head and thorax much narrower than the elytra ; antenna; filiform and simple and inserted upon 



the front, and about as long as the body Ptinus, 8 sp. 



BB. Form cylindrical or sub-globular. Antenna} usually either branched or with the three last 

 joints longer than the others, and inserted before the eyes. 



C. AntennsB simple, but with the three terminal .joints elongated Anohium, 22. 



C C. Antenna* branched in the male, serrate in the female Ptilixi's, 3. 



A A. Autennj* terminating in three larger and somewhat serrate Joints ; tibial spurs distinct ; tar.si 

 apparently 4-jointed. Thorax asperous. Elytra often truncated and toothed behind : 



Bo.sTiacHL's, VJ. 



The Ptinus fur, Linn., is three-twentieths of an inch long, light brown, 

 with two whitish bands across the elytra, interrupted in the middle. The 

 thorax is uneven, having a tubercle on each side and two on the back. 

 This insect feeds upon almost all kinds of dried animal matter, and is 

 often very injurious in museums of natural history. It was originally a 

 native of Europe, but. has become disseminated over the civilized world. 

 We have a very similar species in this country, the humeraUs, of Say, 

 which is regarded by some as only a variety of the European species. 

 We have also another common species, often found in company with the 

 others, in cellars and out-buildings. This is the Ptinus brunnens, and is 

 distinguished at once from the others by being wholly of a light-brown 

 color, and destitute of the bands on the elytra. 



Our most common species of Anobium is the A. tennestriatum, Say, 

 scarcely three-twentieths of an inch in length, of a uniform, cinnamon- 

 brown color, with a microscopically fine silken pubescence, and the 

 elytra with fine impressed lines or striic. This species is also injurious 

 to cabinets and herbaria. It may often be caught upon the wing in or 

 about our houses. 



The genus Bostrichus contains a number of small species, which, in 

 their larva state, are genuine wood-borers, and some of which are se- 

 riously injurious both to fruit and forest trees. The B. hicaudatus, a 



