ON SOME OF THE FOSSIL TETTIGID.E. 175 



character makes it probable that the waters of the 

 ancient lake occasionally dried up in summer. 



The age of these remarkable lacustrine deposits 

 cannot be certainly assigned ; but it is believed that it 

 is not later than the close of the Cretaceous, nor earlier 

 than the last great upheaval of the Tertiaries, during 

 or after Miocene times. Mr. Scudder refers them to 

 the Oligocene. 



The fauna and flora appear to agree partly with 

 those of (Eningen and of Kadaboj in Croatia. Diptera 

 are abundant, including Boynhijlius, Syrphus, and a 

 host of Muscidae. Lepidoptera are few ; but there are 

 wasps, bees, ichneumons, and examples of Chalcis, 

 Chryseis, and Tenthredo. Fish, birds, feathers, and 

 numerous plants help to make up the list of this 

 wonderful natural museum. 



Amongst the nineteen species of Hemiptera dis- 

 covered by Mr. G. M. Dawson in some stratified beds 

 of British Columbia, which are believed to be Oligocene, 

 curiously only two species, contrary to what is usual, 

 are Hemipterous ; whilst of the Homopterous Cercopidae 

 we have the disproportionate number of eleven species, 

 Fulgoridae three, and Aphidae two species. The 

 dimensions of these insects much exceed the average 

 of those known elsewhere in Tertiary times. 



Our own crimson- winged Triecphora bas more than 

 one representative in the fossil state, — FalcBecphora ma- 

 culata and Petrolystm gigantea of Scudder ; both of which 

 insects I have figured in Plate F. The latter is nearly 

 one inch and a half in length, and mai-ked with 

 three broad bands, which still retain some traces of 

 colour. 



For the diagnosis of the numerous fossil species of 

 Tettigidas, I must refer the reader to the illustrated 

 works already cited, and particularly to those of Mr. 

 Scudder. Like most other fossil insects that we have, 

 the legs, head, and many body-parts are here " con- 

 spicuous by their absence," which, coupled with the 

 defective and crushed condition of their abdominal 



