ON SOME OF THE FOSSIL TETTIGIDJE. 179 



in the islands of the Azores and Canaries we yet see 

 the summits of the mountains of this far-off land of 

 the golden west — the Hesperides. 



Speculation apart, the general consensus of opinion 

 amongst botanists is with Sir Joseph D. Hooker, who 

 concludes that the ancient Greenland flora and fauna 

 was more in accordance with a warm European than 

 an American type. Thus the present ice-capped dis- 

 trict of Spitzbergen once yielded flowers of the water- 

 lily, the ape flourished, and the land was green with 

 the Sequoia and clothed with a temperate vegetation. 



A mild climate, reaching into the Arctic circle, 

 has again been recently proved by Mr. Whymper, who 

 not I'mg ago described a new Cercojmmi from the Tertiary 

 fossil rocks of Greenland.* 



The Tettigidffi of these high latitudes, and those of 

 the Baltic which have left their identical bodies in the 

 amber nodules, have long been swept away by the 

 glacial streams which covered the North and much 

 else of the British Isles. Such intense cold must 

 have speedily destroyed all traces of subtropical life 

 and its attendant vegetation. 



Dr. F. A. Walker, in his recent visit to Iceland, 

 could find there no traces of Tettigidae, although in the 

 country round Keyhjavik he obtained several Syrphidse 

 (presumed feeders on Aphides) and a few Noctuae, but 

 no diurnal Lepidoptera. 



Some have thought that the earliest types of insects 

 must have been less specialized than those which 

 came after. There is reason to suppose that the first 

 palaeozoic insects were four-winged ; and that all their 

 wings were of a homogeneous texture. Thus far observ- 

 ation shows that the Hemiptera-Homoptera occurred 

 long before the Heteroptera, in the strata now explored. 

 But we must remember that the Orthoptera and the 

 Coleoptera had then coriaceous elytra and membranous 

 wings, as now. 



The general plan of wing neurations in early insects 



* Phil. Trans, vol. 159, part 39, 56. 1870. 



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