443 



cone or strobilus ; but their original mode of existence is best ascer- 

 tained from the appearance which is yielded by the specimen figured 

 at Fig. 7, where is evidently exhibited the stalk and husks from 

 which the grain or seeds have fallen. The width which this speci- 

 men possesses, making every allowance for compression, will un- 

 doubtedly strike you as much greater than that of any known 

 vegetable, the grains of which are of no larger size than those which 

 are represented at Fig. 6. These seeds, it may be also remarked, 

 differ essentially in their disposition from that which takes place in 

 the spikes of. the grass tribe, having much more the appearance of 

 that of the seeds in the strobili of coniferous plants, which seeds 

 they also appear to resemble in shape. 1 am, therefore, of opinion, 

 that we must be satisfied with considering these as fossils, whose 

 origin must be referred to some hitherto unknown subject of the 

 vegetable kingdom. 



M. Jussieu discovered on a stone, which he found at St.Chaumont 

 en Lionnois, in the earth, near to the coal, an impression, which, 

 he thought, upon close inspection, and comparison with some seeds 

 he had received from Pondicherry, bore an exact resemblance to 

 the fruit-and seed of the Arbor tristis, of travellers, or the Mania 

 Pumeram of the Hortus Malabaricus, p. 35, mentioned also bj 

 Mr. Ray, in his History of Plants, p. 1698. This tree, it appears, 

 grows only in the Canaries, at Malabar, on the coast of Coroman- 

 del, and some other parts of the East Indies*. 



It is a circumstance very difficult of explanation, that silicious 

 petrifactions of the roots of plants, or of trees (Phitolithi Radicum, 

 Rhizolithi) occur more unfrequently than those of any other parts 

 of vegetables which possess a woody hardness. Petrified roots 

 are indeed mentioned by some authors ; but are spoken of under 

 circumstances which imply their rarity. Thus Scheuchzer ha* 



Memoire de 1' Academic Royale, 1723, p. 69. 



