450 



that, as we have already seen, Dr. Parsons V judgment was so per- 

 plexed ; he at first considering that to be a petrified fig, which he 

 afterwards concluded to be a substance of the fungus kind. The 

 representation at Plate IX. Fig. 3, 4, is of a small specimen, being 

 one of those species of this kind of substance, which bears a resem- 

 blance to a small compressed fig. The upper part, Fig. 3, has a 

 gentle rising, as if the stalk had been attached at that part ; and 

 on the under surface, Fig. 4, is a similar depresssion with that which 

 is borne by the corresponding part of a fig. Having been able to 

 mark these substances under many of the various shapes they as- 

 sume, I have no doubt of their being of marine origin, and the 

 residence, and perhaps the workmanship, of animals : they would 

 not, therefore, have been mentioned in this part of our inquiry, 

 but for the sake of showing you that we have now arrived at the 

 examination of substances which, though apparently of a vegetable, 

 are really of an animal nature; and that we have therefore reached 

 the line at which our present labours should cease. 



HAVING now furnished you with what information is in my 

 power respecting real petrifactions of vegetable substances ; it be- 

 comes necessary to say a few words respecting those stones which, 

 from* their accidentally possessing the forms of certain parts of ve- 

 getables, have been by many supposed to have actually derived 

 their figures from the substances which they so much resemble. 

 These stones, the Phytoglyphi of Wallerius, being a species of the 

 Petrificata ficta of Linnaeus, Lithoglyphi of Wallerius, and Lapides 

 Jigurati of others, have, from their great similitude to different parts 

 of vegetables, occasioned numerous mistakes in the writings of 



