343 ORDERS OF PTILOTA. 



of the appearance of the perfect insect. The extremity of 

 the body of these larvae is often furnished with a fleshy 

 retractile tubercle on its under side, which is employed as a 

 seventh leg. When the larva has attained its full size, it 

 generally biu-rows into the earth, where it hollows out an 

 oval cell, within which it is transformed into an inactive 

 pupa, of an uniform whitish colour, with the wings and legs 

 folded upon the breast. The pupa3 of some of the species 

 are, however, naked, as in the Chrysomelidce, whilst others, 

 as Clythra, pass this state within the case which had served 

 for their abode whilst larvae. The duration of these trans- 

 formations, the habitations and economy both of the larva 

 and perfect insect, varies, as may well be supposed, in so ex- 

 tensive a group, in the different families and genera. Arrived 

 at their last state, they possess their full degree of develope- 

 ment, and now the reproduction of their kind is their chief 

 employment. 



Hardly any coleopterous insect has been employed in the 

 arts, but it is questionable whether some of the species 

 might not be rendered useful. The Meloe and the Coc- 

 cinella emit from the mouth and legs a gummy fluid of a 

 fine yellow coloiu", which might be employed in painting. 

 The former insect is of a large size, and sufiiciently abun- 

 dant for experiment, if some of our celebrated chemists 

 would not think the subject beneath their notice. In like 

 manner the Mylahris, Cantharis, or Carabus, might furnish 

 an useful extract of a fine colour. The medicinal properties 

 of the Cantharides are too well known to require detailed 

 description. It is not improbable that many other species 

 possess similar powers. Less useful, but liighly orna- 

 mental, the metalhc coverings of many species may be, 

 and indeed have been, employed in decorating various kinds 

 of trinkets, giving an effect equal to that of gold or precious 

 stones of every shade. By the Indians they are employed 



