TATE — ON THE GEOLOGY OF BEADNELL. 
67 
width and characters are the same throughout the entire length ; it 
occurs in large rounded loops from half an inch to more than three 
inches apart. 
Having found sections showing the interior of this curious fossil, I 
have been able to determine the width of the body, and the distance 
of the articulations from each other. 
This is the most widely distributed of the carboniferous annelids ; 
it occurs in sandstones of the mountain-limestone at Beadnell, Scre- 
merston, Howick, Haltwhistle,* and also in flaggy beds of the millstone- 
grit at Berlin Carr, between Alnmouth and the Coquet. 
Fig. 1. — Upper surface ; the keel-like centre is that portion of the body not 
covered with cirri. 
Fig. 2. — Section showing the articulations of the body ; a, intestinal canal ; 
h, muscular layer and articulations ; c, space occupied by cirri. 
CRASSOPODIA MEDIA (Tate). Plate II. figs. 3, 4. 
Length considerable (upwards of three feet, nine inches) ; usual 
width about four lines ; some specimens are only three lines, others as 
much as six lines wide ; thickness three lines ; width of body two 
lines ; length of cirri one line and a half, twenty of them in the space 
of one inch ; the width and thickness continue the same throughout 
the entire length. 
It occurs in irregular loops and long undulations which occasionally 
cross each other, and is quite distinct from the C. Emhletonia, being 
much smaller and much thicker in proportion to its size j the cirri are 
less crowded and the foldings are more tortuous and irregular. 
It occurs in sandstone at BeadneU, abundantly at North Sunder- 
land, at Newton-on-the-Moor, and at Howick. 
Fig. 3. — Upper siuface. 
Fig. 4. — Section showing the cirri and a cast of the body. 
Nemertites (McLeay). — A. Genus which has been described from 
the Silurian formation ; it is thus defined : — Body very long, linear, 
slender, of nearly uniform thickness throughout, without distinct 
articulations. 
* On the Irthing, near Combe Crag. 
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