PLATE 2, 3, 4. 
fossil they are always alternate, never forked or dichoto- 
mous, and constantly jointed in the same manner as the 
stem. 
■ff. E. lavis has also been confounded with an Entrochite, 
which resembles it In some particulars, but differs in wav- 
ing the stipe conical, with concavo-convex joints — This 
latter Species is common in some parts of England, but has 
not, as yet, been found in Derbyshire. 
2. Joints broken from H. E. Icevis. St. Cuthbei'd s heads. 
The joints are always longer or deeper in proportion to the 
decrease of their diameter : in Entrochita, about orie-fourtli 
the thickness of the specimen above described (fig. 1.) the 
joints are frequently half an inch long; on the contrary, in 
specimens more than two inches in diameter, which I have 
met with, the articulations do not exceed in depth the 
thickness of a shilling. 
3. Fragments of the arms or lateral branches. These are 
rarely found adhering to the main stem. 
4. The common even Entrochite, when the outer coat is 
destroyed. Generally found in cylindrical cavities, as 
represented in the figure. The matrix commonly chert. 
Specimens of this kind arc distinguished by the title of 
Screiv^stones, in Derbyshire, 
B 
