PALEONTOLOGY. 273 



the forms of primitive seas, and of elevated lands. lu sonic 

 cases these organised structures have been preserved perfect 

 in the minutest details of tissues, integument, and articu- 

 lated parts, whilst, in others, the animal passing over soft 

 argillaceous mud, has left nothing but the traces of its 

 course,* or the remains of its undigested food, as in the 

 coprolites.f In the lower Jura formations (the lias of Lyme 

 Regis), the ink bag of the sepia has been so wonderfully pre- 

 served, that the material, which myriads of years ago might 

 have served the animal to conceal itself from its enemies, still 



* [In certain localities of the new red sandstone, in the valley of the 

 Connecticut, numerous tridactyl markings have been occasionally 

 observed on the surface of the slabs of stone when split asunder, in like 

 manner as the ripple marks appear on the successive layers of sandstone 

 in Tilgate Forest. Some remarkably distinct impressions of this kind, 

 at Turner's Falls (Massachusetts) happening to attract the attention of 

 Dr. James Deane, of Greenfield, that sagacious observer vas struck with 

 their resemblance to the foot-marks left on the mud-banks of the adja- 

 cent river by the aquatic birds which had recently frequented the spot 

 The specimens collected were submitted to Professor G. Hitchcock, who 

 followed up the inquiry with a zeal and success that have led to the 

 most interesting results. No reasonable doubt now exists that the 

 imprints in question have been produced by the tracks of bipeds 

 impressed on the stone when in a soft state. The announcement of this 

 extraordinary phenomenon was first made by Professor Hitchcock, in 

 the American Journal of Science, (January, 1836,) and that eminent 

 geologist has since published full descriptions of the different species of 

 imprints which he has detected, in his splendid work on the geology of 

 Massachusetts. Mantell's Medals of Creation, vol. ii. p. 810. In the 

 work of Dr. Mantell above referred to, there is, in vol. ii. p. 815, an 

 admirable diagram of a slab from Turner's Falls, covered with numerous 

 foot-marks of birds, indicating the track of ten or twelve individuals 

 of different sizes.] Tr. 



t [From the examination of the fossils spoken of by geologists under 

 the name of Coprolites, it is easy to determine the nature of the food of 

 the animals, and some other points; and when, as happened occasionally, 

 the animal was killed while the process of digestion was going on, the 

 stomach and intestines being partly filled with half-digested food, and 

 exhibiting the coprolites actually in situ, we can make out with cer- 

 tainty, not only the true nature of the food, but the proportionate size 

 of the stomach, and the length and nature of the intestinal canal. 

 Within the cavity of the rib of an extinct animal, the palaeontologist 

 thus finds recorded, in indelible characters, some of those hieroglyphics 

 upon which he founds his history. The Ancient World, by D. T 

 Aiwted, 1847, p. 173.] Tr. 



T 



