of Edinburgh , Session 1876 - 77 . 
355 
likeness to it were discovered by Mr Dixon, of Unthank,* * * § Northum- 
berland, in fine-grained micaceus carboniferous slabs, in 1838, and 
sent by him to the Newcastle Museum. In 1844, Dr Emmons, f of 
Albany, U.S., published an account of annelids found by him in 
Lower Silurian strata, but none of his figures bear the least resem- 
blance to this. An account is given in the first volume of “ The 
Naturalist” of corresponding markings obtained by Mr Ed. Wood, 
in 1850, from the Northumberland strata, specimens of which were 
sent to the Museum, Jermyn Street, which Edward Eorbes marked 
“Casts of Annelid Tracks.” M‘Coy, who gives in his “British 
Palaeontology ” | careful descriptions of the genera already named» 
does seem to have had his attention turned to these. In 1858, Mr 
Albany Hancock contributed an able paper to the Annals of Natural 
History, entitled “ Remarks on certain Vermiform Fossils found in 
the Mountain Limestone Districts of the North of England.” § This 
paper is illustrated by six well-executed plates, the last two of 
which (xviii. and xix.) bear on the present inquiry. The other 
figures are undoubtedly mere tracks, and Mr Hancock believes 
them to be those of crustaceans, but the grounds for this belief are 
far from clear or satisfactory. Referr’ng to a species of Amphio- 
poda — Sulcator arenarius — he says,— “ While forming its track, 
the animal is never seen ; it moves along a little below the surface 
of the sand, which it pushes upwards with its back, and the arch 
or tunnel thus formed partially subsides as the creature passes 
forward, and breaking along the centre the median groove is pro- 
duced.” Now all that this observation shows is, that a median 
groove is formed in the line of this crustacean’s track, though 
the probability of the realisation of a form like this in such a 
tunnel cannot be admitted. It would imply that the tunnel 
* Since this paper was written I have received from a Fellow of the Society, 
P. Dudgeon, Esq. of Cargen, several annulose specimens, one of which, from 
Upper Carboniferous strata, Haltwhistle, Northumberland, not far from this 
locality, bears a close resemblance to the forms figured by Mr Hancock, and 
referred to below. 
t “ The Taconic System.” By Eb. Emmons, Abany, 1844. 
I “ Contributions to British Palaeontology.” By Frederick M‘Coy, F.G.S., 
Cambridge : Macmillan & Co., 1854. 
§ Annals and Magazine of Natural History, vol. ii. December 1858. 
(Plates xviii. and xix.) 
