510 



J. F. BLAKE ON THE UPPER 



corallina. In spite of the last-named, which is thus seen to have 

 rather a wide range, the fauna is essentially Lower Kimmeridgian, 

 and may be well matched in the body of that clay in England. For 

 purposes of comparison in the basin of Paris itself, the Terebratula, 

 Pholadomya, and Ceromya should be especially noted. Fragments 

 of coronate Ammonites which might belong to A. gigas, recorded by 

 Buvignier, were seen ; and it may be noted that A. longispinus is 

 mentioned as occurring ; but there is nothing except the first-named 

 to unite this to the Upper Kimmeridge of England. Hence, therefore, 

 there is no probability of the overlying rocks being of Portland age, 

 as they are called by Buvignier. 



In this locality the rocks which succeed the Virgulian beds at 

 Dombasle are barren, lithographic, but somewhat argillaceous lime- 

 stones, in remarkably uniform beds of from 8 to 12 inches thickness, 

 with thin bands of intervening clay, thus presenting a well-marked 

 lithological character by which they may be distinguished from the 

 lower lithographic limestones. They become more rubbly towards 

 the top, but, except for lumachelles of small oysters of unknown 

 species, contain scarcely a single fossil. They occupy a considerable 

 area, and must be nearly 100 feet thick ; but even Buvignier only 

 records four fossils : — Ammonites gigas, Pleuromya Voltzii, Cardium 

 Dufrenoycum, and Patella suprajurensis. Nothing higher is to be 

 seen in this part of the country, as the lithographic limestones ex- 

 tend to the alluvial plain separating the Jurassic area from the 

 cretaceous escarpment. 



We may next examine the country 25 miles further south from 

 St. Mihiel and Commercy to Bar-le-Duc. The first-named is celebrated 

 for the magnificent fauna of its Bag-deposits, and has been described 

 separately by Buvignier. The escarpment begins about five miles 

 to the west of the town, as at Apremont ; but inliers close at hand 

 enable us to recognize the Calcareous Grit, here still more nodular, 

 with Ehynchonella Thurmanni and Ostrea dilatata, and the overlying 

 Ferruginous Oolite, retaining the same characters that it has further 

 north. But the limestones which succeed these have a much more 

 extensive development. At the grand section exposed on the de- 

 scent to Apremont, the actual base is not seen ; but the rubbly un- 

 stratified mass appears to begin at once. It is here full of unrecog- 

 nizable Thamnastraaan corals (which appear to have been rolled), and 

 abundance of Hemicidaru crenularis, Cidaris florigemma, Apiocrinus 

 Moissyanus, Terebratula maltonensis, and Pecten vimineus. There is 

 a thickness of about 120 feet, all made of similar material except 

 near the top, where about 16 feet is made of massive crinoidal lime- 

 stone as near Verdun. This latter type, therefore, as there, is sub- 

 ordinate to the Coral Bag ; and we hence learn the age of the magni- 

 ficent freestones of this character worked about seven miles to the 

 south at Lerouville, where the quarries have a 100-foot face, all of 

 the same material, with occasional Cidaris jlorigemma, Terebratula 

 insignis, and other fossils. We note also that, whereas near Yerdun 

 the coral-beds formed the capping to the crinoidal limestones, here 

 the latter lie at the top or nearly so, and no definite position in the 



