CLASSIFICATION OF INSECTS. 17 



the characters which they do have are apparently of such nature 

 as to be suitable as a basis for classification. 



The larva? of the Coleoptera are probably, on the whole, more 

 generalized than those of any other order of holometabolous 

 insects. At any rate, the larva? of the most primitive families, 

 which are included in the suborder Adephaga, are campodeiform 

 and in many cases similar to the adults. As in all larva?, there 

 are, of course, no wings and the trophi, antennae, eyes and legs 

 are much reduced and simplified. In the suborder Rhyncophora 

 or snout-bettles, the larva? are legless and much simplified in 

 structure, and this condition prevails in a couple of other, evi- 

 dently related families. For a long time the larva? of beetles have 

 attracted the attention of entomologists on account of their greatly 

 diversified structure and interesting adaptations. At about the 

 same time, two European zoologists, Ferris ('76) and Schi0dte 

 ('76- '83) published elaborate and beautifully illustrated sys- 

 tematic accounts of beetle larvae, and made available a vast 

 amount of material relating to these insects. Comparatively 

 little was added to this for many years, but interest is again 

 awakening in the matter. 



The work of Schip'dte and Ferris shows very clearly that a 

 complete classification of many families of beetles on the basis 

 of the larvae will be possible. As is well known to all entomolo- 

 gists, the larvae of a good many groups are recognizable at a 

 glance, from their general habitus alone. Of these one series 

 representing the lady-birds or Coccinellidae has recently been 

 treated by Boving ('17) in a systematic way. These larva? are 

 active, predatory forms with well developed legs and \vith various 

 tubercles, spines or processes developed on the thorax and abdo- 

 men. Boving has been able to develop a system of classification 

 based upon many characters which appears to be very satis- 

 factory, although limited as are all studies of this sort by the 

 great difficulty in obtaining extensive series of larva? that are 

 accurately correlated with the imagines. 



A very different type of Coleopterous larvae occurs in the 

 family Cerambycidae, or longicorn beetles. In this group, the 

 larvae are legless, cylindrical creatures, undergoing their entire 

 development in the woody tissue of various shrubs and trees. 



