BLUM ON FOSSIL SNAKE-EGGS. 43 



the kindness to arrange an excursion to the place and show me the 

 exact spot. 



These eggs are found in the Tegel-formation of the district of 

 Offenbach, about half a league from thence, not far from the village 

 of Beiber, in the quarries on the road towards Seligenstadt. 



A brackish water-limestone, which is hereabout exposed in several 

 quarries, exhibits a stratum of eight to ten inches thick, which is 

 distinguishable by its soft loamy nature from the rock lying above 

 and below it. In this the eggs are chiefly to be met with ; for, 

 according to the statement of the workmen, they occur very seldom 

 in the hard strata. The whole rock belongs to the Paludina lime- 

 stone, since Paludina acuta {Littorinella acuta, Al. Braun) com- 

 poses chiefly the mass. These little shells are here always enveloped 

 in a calcareous coating, and are held together by a more or less pure 

 calcareous matrix, so that the rock has a more or less oolitic appear- 

 ance. At isolated spots calc-spar traverses the rock in lines, or 

 disposes itself in druse cavities, in columnar spars, or in crystals. 

 The limestone is partly white, partly more or less coloured yellow by 

 hydrated oxide of iron. Sometimes the colour is arranged in stripes, 

 which traverse the eggs also, when the latter are filled with the 

 matrix. 



The stratum that contains the eggs is moist, and so soft that large 

 pieces can with difliculty be removed ; by exposure to the air it be- 

 comes somewhat harder and gradually becomes white and chalky. 

 The eggs occur in this bed either singly or in groups. There are 

 found also both in this softer, as well as in the harder part of the 

 rock, a large Helix, perhaps H. Mattiaca, Steininger, and more 

 plentifully a small Helix ; also Clausilia bulimoides and JDreissenia 

 Brardi. 



From what we have said of the characters and contents of these 

 fossils and of the conditions under which they exist, it results that 

 all idea of their inorganic concretionary origin must fall to the ground. 

 Concretionary bodies are formed from within outwards, but here 

 exactly the opposite has taken place ; lime in solution has permeated 

 the parchment-like shell of the egg and has been gradually deposited 

 on its inside, and thus preserved the form of the egg after the organic 

 substance itself had disappeared. 



I consider therefore these fossils to be the eggs of snakes, perhaps 

 of a Coluber ; they are, however, somewhat too large for eggs of 

 the Colubers or lizards now existing in the neighbourhood. 



Lizards lay their eggs in warm sand, but many snakes lay them in 

 moist ground or mud, even under water. Such animals could have 

 lived here, on the banks of the Maine and the Rhine, and have de- 

 posited their eggs in the calcareous mud, where perhaps an increase 

 of calcareous matter not only prevented the hatching, but furthered 

 the petrification of the eggs. [T. R. J.] 



