LOWER MAGNESIAN LIMESTONE OF SUNDERLAND. 219 
(both of the cast and the impression) is covered with moderately 
fine, thread-like anastomosing, transverse striz. 
I give a name to this fossil chiefly for the sake of convenience. 
It would seem from its general character to belong to the Annu- 
lata, though to what particular group, it would perhaps be diffi- 
cult to say; neither would it be wise to assert whether we have 
in this fossil the petrified form of Serpulites anastomosis, or 
merely that of its track or dwelling-place. 
A Permian fossil that is probably nearly related to this occurs 
at Tunstall Hill, in Middle Limestone; at East Thickley, in 
Lower Limestone; at Hooten Pagnell, Yorkshire, in Lower 
Limestone; and at Leimnitz, near Gera, in the zechstein dolo- 
mite of Saxony. ‘This fossil is considerably larger, and evi- 
dently a different species; bat both it, and the one just described, 
as well as another which I have from Tunstall Hill, all appear to 
belong to animals that made tracks in the limestone mud of the 
Permian period. The Saxon specimens have been described by Dr. 
Geinitz as a plant under the name of Palaophycus insignis.“ 
The first of the above fossils which I found were the Stra- 
parollus and the Chonetes, neither of which I had ever met with 
in Permian rocks before. The Carboniferous facies of these 
forms almost caused me at first to suppose that I had come upon 
a colony of Carboniferous recurrents. Further search, however, 
brought to light better known Permian species, such as Leda 
speluncarra and Spirifera Urii, which somewhat modified my first 
thoughts. Nevertheless, Sp. Urii is a Carboniferous recurrent, 
and so is Camarophoria crumena and Fenestella retiformis, which, 
with the Chonetes and Straparollus, form about half of the species 
found—so that there may still be something in the idea first 
originated. 
But putting aside all ideas of the Carboniferous descent of 
this local fauna, I may nevertheless remark that it differs as a 
group of Permian species from all other groups with which I 
am acquainted. The prevailing species are either wholly new 
to Britain, or such as are comparatively rare in other localities 
where they occur. And such of the Permian types as are 
(5) Dyas, vol. II, 
AaB 
