220 WINOOSKI MARBLE. 



shell in all directions so that the appearance at first 

 glance is that of a number of different species, but thus 

 far I think but one species has been certainly identified, 

 though it is probable that there are more. The fossils, 

 as they are white, show distinctly on the red background 

 of the rock after it has been sawn, but as fragments of cal- 

 careous rock of white or light color of all shades and 

 sizes are scattered through the red cementing material, 

 fossils are not very easily distinguished from the frag- 

 ments on a fractured surface. 



They do not appear to be at all common as a diligent 

 search has thus far enabled us to procure but a very lim- 

 ited number of pieces of stone containing them. Nor do 

 they cover large patches in the rock usually, most of the 

 clusters are not larger than -the palm of the hand and 

 such a cluster may occur alone in the midst of a large 

 slab of marble. In one specimen which I found they 

 covered, in some places so thickly as to form a compact 

 mass, a surface twenty inches in diameter, but I have 

 seen iio other specimen that approached this in size. 



They never occur sprinkled through a large mass of 

 stone but always in clusters having from thirty to fifty 

 sections in a space an inch square. Nor do they form 

 thick la3ers, very rarely do they appear at all on both 

 sides of a slab an inch in thickness; usually they do not 

 seem to form a layer more than half an inch in depth. 

 The marble occurs in "bed§" from one to six feet thick, 

 the outer surface of the bed or layer is, to a slight depth, 

 of light color and shows to but a slight extent the charac- 

 ter of the stone. It is near this outer surface of the blocks 

 that the Salterella occurs. I believe that in no case have 

 any been found in the middle of a block ; so my own inves- 

 tigations have shovv'n and so I am assured by Mr. Barney 

 from whom I have obtained several pieces. 



