59 JURASSIC OR OOLITIC SYSTEM. 



fig. 83), a flying saurian, whose head and neck gave it the semblance 

 of a bird, and its tail was like that of a mammal, while its extremities 

 were analogous to those of a bat ; it was capable of walking and 

 flying, and, perhaps, of climbing steep rocks in pursuit of food. 



41. With the remains of these singular animals are found, in the 

 lias of Lime-Regis, on the coast of Dorset, England, an immense 

 quantity of coprolites (from the Greek kopros, dung, and lithos, 

 stone), which probably belonged to them : sometimes their intes- 

 tines are found in their skeletons ; and we also find, in these, the 

 remains of fishes and other reptiles, clearly showing how the 

 aquatic species were nourished. The remains of insects are found 

 with those of the pteroda'ctyli at Solenhofen, in Franconia, also 

 showing what was the food of these animals. 



42. Saurians resembling crocodiles were much less abundant in 

 this epoch, although we find, in the lias, remains which prove 

 their existence. The me'galosau'rus (from the Greek mcgas, great, 

 and sauros, reptile) partook of the nature of the crocodile and 

 monitor, and must have been from fifty to sixty feet in length. 



43. Ink-bags of considerable size (fig. .84), ana- 

 logous to those of the cuttle-fish, are also found. In 

 the lias of Lime-Regis, the dorsal bones of the calmar 

 are also met, with other traces of this genus, as well 

 as of belemni'tes. The ink or se'pia, which may be 

 obtained from these fossils, is as good as that pre- 

 pared from the recent cuttle-fish, and has been used. 



41. THE JURA/SSIC OR O'OLITIC SYSTEM. Oolite 

 (from the Greek don, an egg, and lithos, a stone), is a 

 granular variety of carbonate of lime, frequently called 

 roc-stone, from its resemblance to a fish-roe, or egg-bag. 

 n- ^6 frequency of the occurrence of this particular 

 'bag. n form of limestone in a great series of deposits, has 

 caused the name of o'olilic to be applied to the whole series. 



45. The o'olitic or jura'ssic deposits (the Jura-kalk of German 

 geologists), are divided into several groups, which are distinguisha- 

 ble from each other by their relative position in the scale of eleva- 

 tion, but more particularly by the fossils found in them ; the re- 

 mains which are characteristic of the preceding groups, are not 

 met with in this. The o'olite is divided into the lower, middle, and 

 upper o'olites. 



46. The lower o'olite, the first in the series of o'olitic deposits 



40. What is a Pteroda'ctylus? Where is it found ? 



41. What was, probably, the food of the Pteroda'ctylus? 



42. What was the Me'galosau'rus ? 



43. What other fossil substances are found in lias? 



44. What is o'olite? 



45. How is the o'olitic system divided ? How are the divisions recognised ? 



46. Of what does the lower o'olite consist? By what foseil is it charac- 

 terized ? 



