ORIGIN OF THE COLEOPTERA, ETC. 
303 
form of the body and its appendages, both explain the metamorphosis of 
insects in general and also the differences between the larval forms of 
the different orders. 
The following view will convey an idea of the larvae of the Coleo- 
pterous families which in a general way correspond to the different larval 
stages of the Meloidae; it being understood that the resemblances are 
suggestive and general, and not to be accepted in a too literal sense. 
1. Primitive triungulin stage. 
! Iu Meloe more like Campodea than 
in Epicauta. 
Meloidae. 
Stylopidae. 
2. Carabidoid stage. 
f Cicindelid®. 
Carabidae, Dytiscid®, Hydrophilidae. 
J Silphidse, Nitidulari®, Dermestid®, 
j Coccinellid®, etc. 
Elateridae, Lampyridae, Telephorid®, 
Cleridae, Pyrochroid®. 
( Histerid®. 
3. Scarab®idoid stage. < Scarab®id®. 
( Ptinid®. 
^ Cerambycid®. 
4. Coarctate stage, more or less I Mordellidaf 80 ' 
cylindrical and apodous. < c urcul i 0 nid®. 
/ Scolytid®. 
Fi’om the facts and considerations which have been presented, we 
are disposed to believe, subject, of course, to future correction, that the 
primitive Coleoptera were carnivorous forms, and that the scavenger 
and phytophagous forms have been derived from them, and are there- 
fore secondary products, and as a whole of more recent origin. 
The primitive form of beetle was probably a Staphylinus-like form, 
with a long, narrow body and rudimentary elytra, and carnivorous in 
habits. This has been suggested by Brauer, 150 though it occurred to us 
before meeting with ( his views. 
Though the earliest beetle known is a Carboniferous weevil-like form, 
yet we imagine the Coleopterous type became established in Devonian 
or Silurian times, when there may have existed the prototypes of the ear- 
wigs and beetles; for the two types may have branched off from some 
Thysanurau form. On the other hand, the primitive Coleopterous larva 
may have sprung from some metabolous Neuropterons form. The larva 
of Gyrinus has a striking resemblance to that of Corydalus and other 
Sialid®, so much so that a terrestrial Carabidous form most probably 
was of Neuropterons origin, as indicated in our diagram. 
Origin of the Diptera , Lepidoptera, and Hymenoptera . — The Euglossata 
probably had a common origin in the first place from the metabolic 
160 So wil’d uns der Staphylimie ale eino dor liUesten Kliferfornien gelten, etc. Betra htnngen liber die 
Verwandlung der Insokten im Sinne der Descendenz-Tlieorie, von F. Bruner, Yerli. k. k. zool.-bot. 
Ges., Wien, 1869, p. 313. 
