Dr. Troost on Amher, ^-c. 11 



surface rough, resembling often in roughness and colour, 

 the unripe fruit of the orange tree known to the druggists 

 by the name of bitter oranges; sometimes its surface re- 

 sembles the bark of some oak limbs. This surface is over- 

 spread with small openings or round holes of two sizes, one 

 size large enough to admit of a large pin, the other, one- 

 fourth of the size. These holes are arranged somewhat in 

 this manner \ \ ■ , and are the openings of interior cells of 

 an irregular oval shape. There are four of these openings 

 in every cell, one in the centre of the comb being in con- 

 tact with the branches around which the matter or substance 

 is deposited, and three on the outside, being the openings 

 above mentioned, of which the centre one is the largest. 

 It would appear that these four openings were formed by 

 the female insect on depositing her eggs. The young in- 

 sects, on being hatched, appear to have fed on the sub- 

 stance, and to have eaten through the investing coat, by 

 which operation one of the openings has become larger.; 

 leaving a hollow bag. The substance of which these nests 

 are made is of a resinous nature, possessing the same chem- 

 ical properties as amber. The cavities and surface are 

 often decked with minute crystals of pyrites. The colour 

 of the internal part varies, probably, according to the change 

 it has undergone from its long stay under ground, or from 

 other unknown agencies — some of them appearing to have 

 undergone a partial fusion, in m hich case, the internal colour 

 is black, and partly charred. Some others seem to be in a 

 state approaching to their primitive appearance, the colour 

 varying then in every shade of yellow, from whitish yellow 

 to orange. 



This bed contains also, a fruit bearing some resemblance 

 10 a bean, but so much disfigured, that I cannot ascertain to 

 what species it belongs. 



The stratum of lignite containing these fossil remains 

 vests on an argillaceous sandstone, from two to five feet in 

 thickness, embracing small masses of pyrites. The surface 

 of this stratum is very hilly, and is neither intermixed with 

 lignite at its line of junction, nor is the least fragment of lig- 

 nite perceptible through the whole bed : hence, it may be 

 conjectured that the lignite has been deposited after the ar- 

 gillaceous sandstone was formed, and is, therefore, a sepa- 

 rate formation. 



