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the small and even minute size of the great majority of the insects, 

 and, indeed, of the whole of the Coleoptera which have been passed 

 under review, the idea that we have before us the wreck of an 

 insect fauna of a temperate region is at once raised ; for, although 

 it would be rash to assert that a mass of the existing tropical 

 insects might not be accumulated in which a large quantity of 

 minute beetles and flies would not be present, yet I cannot conceive 

 any process either arising from currents of water or chemical disso- 

 lution of insect matter, which would carry off or destroy the many 

 gigantic forms of insect life always occurring in the tropics. The 

 fossils before us show abundant evidence of the presence of numbers 

 of lignivorous species such as Elatericlce and Buprestidce ; but we 

 nowhere find amongst them traces of the great Lamellicorn and 

 Longicorn Beetles. Herbivorous insects also occur in considerable 

 numbers, but we do not meet with the gigantic Grasshoppers and 

 Locusts of tropical climates." Professor Westwood goes on to 

 observe that the question of by what means such masses of insect 

 remains could have been brought together, as are found in the 

 slabs of stone from this formation, is one for Geologists to decide. 

 Entomologists, however, are aware that sudden inundations, or 

 the rapid rising of rivers, are sure to bring with them vast numbers 

 of insects, which are carried away by currents in vast numbers, and 

 congregated together in masses. It appears, according to Professor 

 Westwood, that with the exception of the gigantic winged ants 

 and the wings of monster dragon-flies, that there is a very general 

 conformity between the insects from the Dorsetshire Purbecks and 

 those of Wilts and Bucks. There would, however, appear to have 

 been a great difference in the manner of disposition of the strata 

 of the two districts, as evidenced by the remarkable contrast 

 presented by the state of preservation of the insect fauna of the 

 Wiltshire Purbecks, and that of the insect fauna of the Dorset 

 Purbecks. In the form,er, numbers of specimens are in a fair state 

 of preservation, while in the latter, the remains consist of almost 

 always of fragments of wings, elytra, or bodies. It appears from 

 a careful examination of the fossil insect remains from these for- 



