PLATE 38, 39, 40, 41. 
tire, having only a slight wave in front, or in that part 
of the shell near which the siphuncle is situate. The 
siphuncle simple, small, and cylindrical; placed between 
the centre and the edge of the dissepiments. 
Frequent in the black marble at Ashfoi'd; and is also 
found sometimes in the common limestones. 
Fig. 4. A specimen bedded in a mass of black marble. 
The lower chambers broken, so as to show their siphuncle 
or pipe of communication. 
This species varies considerably in size. I have seen it 
more than two feet in length, and eight or nine inches in 
diameter, at the larger extremity: but its more usual size is 
that of the drawing. 
The crocodile, said to have been found in the limestone 
qt Ashford*, appears to be nothing more than a particularly 
large specimen of this, or some other Orthoceratite : prob- 
ably the species we have before figured in the 38th plate. 
The present Mr. Watson, of Bakeivell, informs us, that, 
some years back, on showing a specimen of this fossil to 
his uncle Mr. Henry Watson -f, he was assured by him, 
that it in no respect differed from what he had himself 
found and considered to be the tail of a small crocodile, as 
* See Whitehurt’s Theory of the Earth — Pilkinton’s Derbyshire, &c. 
t The first proprietor of the Marble Works at Ashford. 
