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be considered as satisfactory evidence that land was not far distant 

 at the time they became embedded ; and the abundance of other 

 terrestial remains, usually accompanying these fossils in marine 

 formations, leaves but little doubt upon the subject. One notable 

 exception to this rule is the continental formation known as the 

 *' Solenhofen Slate " of Bavaria (belonging to the Upper Oolite), 

 in which the remains of insects are said to be mixed up, almost 

 exclusively, with the debris of the marine animals and plants. 

 Numerous lacustrine deposits have been discovered in the middle 

 of the marine formations, constituting the greater part of the 

 Jurassic system, which are supposed to indicate the situation of 

 ancient islands. If this supposition be correct, the presence of the 

 remains of terrestrial animals and plants in marine formations is 

 easily accounted for. 



Before proceeding to review the various strata of the period 

 in which fossil insects have been detected, I think it may not 

 be out of place to call attention to the striking diflference in the 

 state of preservation of the insects from EngUsh formations to 

 this period, with that of those from one of the most important of 

 the foreign formations {i.e., the Solenhofen Slate). On the 

 subject of the deposition of the Solenhofen insects, I cannot do 

 better than quote Dr. Hagen,* who observes, " on comparing the 

 insects of Solenhofen and Eichstadt with those of England, there 

 appears, in the first place, a difference which may possibly admit 

 of interesting inferences ; the insects of the Bavarian strata are 

 almost universally preserved entire ; wings, legs, head and 

 antennae are in their proper places ; most of the Lihellulce have 

 their wings expanded. He who has noticed on the sandy shores 

 of the Baltic how depositions of insects are now taking place, will 

 admit that the insects of the Solenhofen strata were already dead 

 when deposited." The insects would be, as now, driven by the 

 wind into the sea, thrown on the shore dead or dying, and there 



*See a paper read by Dr. Hagen before the Geological Section of the 

 British Association at Manchester, September, 1861, and see the 

 Entomologists' Annual for 1861. 



