143 



name of Sauro-copros to the so-called bezoar stones of the lias at 

 Lyme Regis, which are derived from the Ichthyosauri ; and the name 

 of Hyaino-copros to the Album Graecum of the fossil hyaena. 



The form and mechanical structure of the balls of Sauro-copros, 

 disposed in spiral folds round a central axis, are so similar to that of 

 the supposed fir-cones or Iuli in the chalk and chalk marl, that the au- 

 thor has concluded that these so long misnamed Iuli are also of faecal 

 origin. On examination he finds many of them to contain the scales 

 of fish j and Dr. Prout's analysis proves their substance to be digested 

 bone. The spiral intestines of the modern shark and ray afford an 

 analogy that may explain the origin of this spiral structure ; and the 

 abundance of the teeth of sharks and palates of rays in chalk ren- 

 ders it possible that the Iuli may have been derived from these 

 animals. For these the provisional name of Copros iuloides is pro- 

 posed. In the collection of Colonel Houlton, of Farley Castle, are se- 

 veral specimens of the Copros iuloides from the quarries of Maes- 

 tricht. 



The author has also recognized two other varieties of these faecal 

 substances in a collection of fossils brought from the fresh-water for- 

 mations near Aix in Provence by Messrs. Murchison and Lyell. 



The author concludes that he has established generally the curious 

 fact, that, in formations of all ages, from the carboniferous limestone 

 to the diluvium, the faeces of terrestrial and aquatic carnivorous ani- 

 mals have been preserved ; and proposes to include them all under 

 the generic name of Coprolite. 



The examples he produces from the carboniferous limestone, the 

 lias, the Hastings sandstone, the chalk marl and chalk, the Maestricht 

 rock, the fresh-water deposits at Aix, and the diluvium, are taken 

 respectively from the several great periods into which geological for- 

 mations are divided. 



