6 A COMPARISON OF THE FOSSIL INSECTS 



Returning again to the Odonata, we find that of the 

 Lihelhilina there are 4 species 14 specimens. 



It is hence certain that the Gomphina and Calopterygina 

 have been much the richest both in individuals and in species. 

 This proportion is not surprising to those who have attended 

 particularly to these families of insects. For these very 

 families exhibit such curious forms, between which the 

 intermediate species are wanting, that it was rightly suspected 

 the missing links would be found in the Fossil Fauna. 



The Go7nphid(e of Solenhofen principally belong to species 

 which come near the genera Pefalia, Phenes, and Petalura, 

 thus to genera of which at the present day a few species occur 

 in Chili and Australia, and differ strikingly in many respects 

 from all other genera. 



It is of importance to notice that the specimens of Gom- 

 phidce from the English strata (Brodie, Foss. Ins. PI. 5, fig. 

 7, PI. 10, fig. 3, and Westwood, Quart. Jour. Proc. Geol. 

 Soc. 1854, vol. X., PI. 15, fig. 3) come very near both in 

 form and size to the most plentiful of the Solenhofen species, 

 Petalia longialata, at least as far as can be judged from the 

 fragments. The Fossil Gomphina of Soleilhofen are gene- 

 rally very large, and some are truly gigantic — 4 inches in 

 length, with an expanse of wings of^4| inches. 



The Calupterygina of Solenhofen are divisible into two 

 groups; one, containing four species, comes nearest to the 

 genera of the group Euphcea, yet the species cannot be 

 located in any existing genera ; the second forms the singular 

 Meterophlehia of Westwood ; the most frequent Solenhofen 

 species, S. eximiay comes so near the English species 



