352 JMisiittlaueuus IntelHgeitce. 



lected, and presented to the Academy of Sciences, by M. Cu- 

 vier, and are now in the King's Cabinet. 



6. Lignite. — M. Becquerel has examined and published an 

 account of a stratum of fossil-wood, occurring at Auteuil, in 

 the neighbourhood of Paris, which seems of great extent. 

 it contains interspersed here and there succinite, and crystals, 

 supposed to be of mellite ; but the exact nature of which has 

 not been ascertained. 



" This stratum of lignite contains trees still entire in their 

 forms, some of considerable length, and varying in diameter 

 from six to eighteen inches. The space between them is filled 

 with a black sulphureous and bituminous clay. They are pene- 

 trated by pyrites, which are sometimes so abundant as entirely 

 to replace the ligneous part, and which decompose with great 

 rapidity on exposure to the air. Sulphur is found there in a 

 pulverulent form, and there are also saline efflorescences. 

 Succinite occurs in rounded pieces from the size of a millet- 

 seed to that of a hen's egg. It is yellow and transparent, but 

 the workmen sometimes find it whitish, yellow, and translucid. 

 That which I collected at the place from amongst the lignite 

 was pcifectly transparent. There is found also in this stratum, 

 a crystalline substance, of which the existence will be interest- 

 ing to mineralogists and geologists, for, if not mellite, it is a 

 new substance. It is found in small honey-yellow crystals 

 transparent, and adhering either to the surface of the lignite, 

 or occurring in its interstices. These crystals, though very 

 small, are very perfect and regular ; they occur generally on 

 the portions containing least pyrites. They are found some- 

 times in the same piece with the succinite. They are of various 

 forms ; the most common are the octoedron, which appears to 

 me regular, the acute octoedron, and the transposed octoedron, 

 a form which has not yet been observed in the mellite. This 

 circumstance, and that of the form which appears to me a re- 

 gular octoedron, induce me to suppose, that it ought not to be 

 confounded with the mellite. It may be named provisionally 

 xylocryptite , expressive of its being hidden in fossil wood." 



