62 GEOLOGICAL MEMOIRS. 



that the Ant-swarms did not suddenly perish from outbursts of steam 

 or from any other such-hke cause, for all the individuals of a swarm 

 would in that case have fallen together into the water and have be- 

 come fossilized. This probably was not the case, as the males have 

 for the most part escaped. It is also rendered unlikely by the cir- 

 cumstance that in (Eningen large groups of Ants are never found 

 together in one stone, but generally only a single specimen, or at the 

 most two or three. At Radoboj a greater number of individuals 

 often lie together ; but for this, as we shall see, there is another ex- 

 planation. 



3. At Radoboj slabs of stone often occur on which a great number 

 of organic remains are assembled together. There are found, for ex- 

 ample, on one stone of a few square inches, one specimen of Formica 

 pinguis, three of F. pinguicula, one of F. Hesione, one of i^. Telamon, 

 three of F. ophthalmica, one of F. oculata, one of F. Hecuba, one of 

 F. Priamus, one oi Bemhidium, and various fragments of plants. On 

 another stone we find Foimica puinila, F. pumilio, F. pinguicula^ 

 F. ohscura, Amphiotis bella, Harpalus tabidus, a Gnat, and a Bu- 

 prestis. We often find on the same stone leaves of trees, and still 

 more abundantly various- sized fragments of Cystoseirites communis ^ 

 linger, a marine Alga, which is one of the most abundant plants at 

 Radoboj. This clearly proves the former presence of sea-water, into 

 which the land-animals fell ; and hence we can explain why the larvse 

 of the Lihelhdce are absent here, which play so important a part at 

 CEningen. In the place of the larvse we have at Radoboj some full- 

 grown Libellulce ; these animals, therefore, were existent at both places 

 at the same time. There was evidently at Radoboj during the tertiary 

 epoch an arm of the sea into which a river flowed, and in which river 

 the larvae of the LibellulcB had lived, together with water-beetles, a 

 pair of which I here found fossil ; for as these insects never inhabit 

 sea-water, but live only in fresh water, the circumstances of the case 

 point to just such an inflowing river-stream at this place. The con- 

 dition of the organic remains bears evidence to this former distribu- 

 tion of land and water at this place. In such an arm of the sea with 

 a river flowing into it, the sea-plants would have been here and there 

 drifted to shore, together with masses of land-plants and the animals 

 that had perished in the water, where they must have lain in great 

 confused heaps promiscuously washed up. And indeed in suchwise do 

 we meet with them on the afore-mentioned slabs of stone, which dis- 

 play just such confusedly-arranged and drifted masses of plants and 

 animals. 



The organic remains do not occur under such circumstances at 

 (Eningen. It is only the larvae of LibellulcB that we here sometimes 

 meet with in great assemblages, which however are only such as those 

 in which these animals are found living at the bottom of the existing 

 ponds and ditches. And hence we have an additional proof that at 

 CEningen a small quiet lake existed, the water of which was subject 

 only to trifling motion. 



4. A fourth point worthy of consideration with respect to the fossil 

 Ants is the great abundance of the individuals. From Radoboj and 



