ARTICULATA. 151 



bottom should be smoothly covered with sheet cork, corn-stalk pith, the soft 

 root of the southern tupelo, or the wood of Agave americana. If soft white 

 pine is used, a small hole must be made with an awl before a specimen can 

 be inserted. The depth of the drawers will depend upon the length of the 

 pins used. The German insect pins are If inches long, and are preferable 

 on account of their toughness and elasticity, in which they excel the 

 English and French pins. The pin that holds the insect will also pass 

 through the label. A piece of camphor wrapped in gauze or other thin 

 material should be placed in one corner of every drawer, and should it be 

 found from the dust beneath a specimen that there is an enemy at work 

 within it, it should be removed and subjected to a heat nearly equal to 

 that of boiling water. This may be done by placing it in a covered tin 

 vessel, which may be innnersed in another containing hot water. A good 

 wash to destroy moths and the various larva3 found in collections, is com- 

 posed of one part of oil of turpentine, and six of camphorated alcohol. 

 A few globules of mercury are sometimes placed in the drawers to prevent 

 the ravages of the minute louse-like Trodes ijulsatorius. Constant care is 

 necessary to prevent collections from being destroyed, and new specimens 

 should be introduced with great caution, as they may contain eggs which 

 M'ill produce a destructive larva. 



Much of the history of insects remains to be known, and larvae should be 

 drawn and described, and kept until their final change shows what they are. 

 By a system of numbering, valuable observations may be made without a 

 knovdedge of the scientific name of an insect. This knowledge comes 

 slowly, and the observer should not relinquish his studies because he meets 

 with diificulties. New discoveries are made every year in Europe, whose 

 entomology has been long studied by numerous active observers, and still 

 more important ones would reward a similar class upon this continent, 

 where so much remains to be made known in the various orders of 

 insects. 



Coleoptera are widely spread, the largest species being found between the 

 tropics. They seem not to be as hardy as some of the l^europtera and 

 Diptera, none being found in Spitzbergen and similar localities. The 

 richest collection of Coleoptera is that of the Royal Museum of Berlin, 

 which contains 40,000 species. 



Various classifications of the Coleoptera have been proposed, not one of 

 which has acquired an exclusive popidarity. Here we follow that of 

 Westwood, which agrees better with the arrangement of Stej)hens and 

 Latreille, than with that of Erichson, which will probably supersede them 

 in time. 



The order is divided into sections (Westwood Shuckard), according to 

 the joints of the tarsi, which, although they are not uniform in every case, 

 aftbrd a remarkably good general characteristic. This gives the four sections, 

 Pentamera^ Heteromera^ Tetramera^ and Tnmera. Macleay divides the 

 Pentamera into two groups (named tvihes by Westwood), ' Cliilopodomorphoj 

 and CMlognathomorjyha^ according as the larva resembles Scolopendra and 

 Julus ; and he endeavors to divide the remaining sections in an analogous 



355 



