ECBINITES. 213 



The stalks of these fossils are mostly smooth, but the bodies 

 themselves are beset Avith rows of mimite knobs, placed in the 

 quincunx form. The rows are often connected by slender tln-eads, 

 running from the stalk to the opposite extremity. This extremity is 

 sometimes blunt and sometimes rather pointed ; the bodies being in 

 various shapes, compared to cucumbers, olives, &c. 



Fig. 7 (PI. VI) from Malton, is a good specimen of a spinite. It 

 is thicker than most fossils of this class ; but there are others of a 

 more rounded or bulbous form, like olives, of a much greater thick- 

 ness. Those which occur most frequently are more slender than No, 

 7, and longer in proportion to their thickness; and their ends are 

 less blunted. 



Fig. 8 exhibits a singular group of spinites, from Kirkby Moor- 

 side. They have a gentle bend to one side, which seems quite 

 natural, there being no mark of violence, to indicate that they have 

 been forced out of their proper shape. In other respects, they are 

 exactly similar to the common spinites. 



These bodies are invariably found in the state of spar, and, as in 

 many other sparry petrifactions, their cross fracture is always oblique, 

 their crystals never cutting their axis at right angles. In many 

 specimens, a central hole is perceived, passing from the stalk to the 

 point, like the pith in trees, as is the case in the vertebral columns 

 of the encrinite. These fossils are found in great quantities mixed 

 with corals, and they might have been classed with zoophytes, had 

 not their connection with the maramillated echinites of the cidaris 

 family been fully established, as may be seen in Parkinson's Organic 

 Remains, Vol. III. 



In some specimens of blue limestone, found in the alluvium, we 

 discover small hair-like substances mixed with shells, generally 

 brown and shining, with a lustre like cojDper. These acicular spines, 

 if we may so call them, are some of them in contact with roundish 



3 G 



