FOSSIL INFUSORIA. 



the race of the Xanthidia is evident from the resemblance they bear to the draw 

 ings of the living specimens, figures 40 and 41. Five specimens were found in this 

 fragment of flint, varying in diameter from one-three hundredth to one-five hundredth 

 of an inch. 



Fig. 95. 



Fig. 94 



PEAT BOGS. The peat bogs both of ancient and modern origin, are frequently 

 found to contain beds and layers of a white flinty earth, which is entirely composed 

 of the shells of protophytes. In many swamps of Ireland and England, earthy strata 

 of this peculiar nature have been found ; and in this country, Prof. Bailey has dis 

 covered near West Point a deposit eight or ten inches thick, and in all probability 

 several hundred yards in extent, wholly made up of the flinty shells of the diatoma- 

 ceous organisms, in a fossil state. &quot; This deposit,&quot; says Prof. B., &quot;is about a foot 

 below the surface of a small peat bog. immediately at the foot of the southern escarpe- 

 ment of the hill on which the celebrated Fort Putnam stands. In draining this 

 bog a large ditch was dug, and among the matter thrown out, my attention was at 

 tracted by a very light white or clay colored substance, which, when examined 

 closely in the sunshine, showed minute, glimmering, linear particles. On submitting 

 it to observation, by means of a good microscope, I found it to be almost entirely 

 composed of fossil organisms. There can be 

 no doubt, that in this place there are several 

 tons of the shells of beings so minute as to be 

 barely visible as brilliant specks, when care 

 fully observed in a strong light by the naked 

 eye. Hundreds of years must have elapsed 

 before such an accumulation could have been 

 made. 1 The kind of shell that is most abun 

 dant in this earth is delineated in figure 94, 

 which represents a ^specimen magnified three 

 hundred and fifty times ; and in figure 95 is 

 shown the appearance presented by a little 

 of the earth diffused in a drop of water, and 

 magnified about fifty times. The earth is 



here seen consisting of a great number of shells of various shapes and 

 sizes, clearly proving that the deposit is nothing more than a vast assem 

 blage of immense multitudes of minute fossil structures. 



FORAMINIFERA. The fossil shells of these minute forms of animal life now exist 

 in such profusion, rising into mountains, and extending in broad and deep layers 

 beneath the surface of the earth, that it has been observed by the learned Dr. Buck- 

 land, &quot; that the remains of such minute animals have added much more to the mass 

 of materials which compose the exterior crust of the globe, than the bone of ele 

 phants, hippopotami, and whales.&quot; 



In these vast collections the Nummulites largely prevail. They are divided into 

 numerous species, varying in dimensions from the size of a crown-piece to that of a 



