66 
THE GEOLOGIST. 
a little northward of Ebbs Nook. They are seen also in other sand- 
stone beds of the section, as well as in other localities in Northum- 
berland. Though similar annelids are not unfrequent in Palaeozoic 
rocks, they have been but seldom noticed. Sjjecies from the Silurian 
rocks have been described by Sir R. Murchison in his great work the 
" Silurian System," by Professor McCoy in Sedgwick's " Synopsis of the 
Classification of British Palseozoic Rocks," and by Mr. J. W. Salter in 
the Quarterly Journal of the Geological Society. Few distinct descrip- 
tions have been given of such forms in the Carboniferous formation ; 
the only notices I know of are contained in a paper by Mr. E. W. 
Binney, " On some Trails and Holes formed in rocks of the Carbo- 
niferous Strata ;" * and in an excellent popular " Account of a large 
fossil, marine worm, occurring in the Mountain-limestone district in 
Wensleydale, Yorkshire," by Mr. Edw. Wood, F.G.s.f Mr. W. Lee 
also refers to annelid-borings, in a paper on what he calls " Fossil 
Footprints in the Carboniferous system." J Having carefully examined 
the annelids in the Mountain-limestone formation of Northumberland, 
I am able to distinguish four distinct forms ; two of them are i-efer- 
able to Crassopodia (McCoy), a genus which has been found in Silurian 
beds, and which may be thus defined : — Body long ; formed of exces- 
sively short, numerous, wide segments, from which arise very long, 
delicate, crowded cirri forming a broad dense fringe on each side, com- 
pletely concealing the feet. These annelids appear to belong to the 
order Dorsibranchiata of Cuvier, and are allied to the nereides which 
now inhabit our coast. These latter are marine worms which creep 
in a serpentine manner, and even swim by successive undulations of 
their bodies or by agitating their appendages. 
CBASSOPODiA EMBLETONiA § (Tatc). Plate 11. figs. 1, 2. 
Length unknown (upwards of two feet) ; width one inch ; thickness 
not exceeding four lines ; width of body five lines ; articulations three 
lines apart ; cin-i about four lines long, crowded, there being twenty- 
four in the space of one inch. There is no appearance of a head ; the 
* Memoirs of the Manchester Philosophical Society, vol. x. p. 181. 
t The Naturalist, Nos. I. and II. pp. 14 and 41. 
J Proceedings of tlie Yorkshire Geological Society, vol. ix. p. 409. 
§ I have named this after my esteemed friend, Mr. R. C. Embleton, the accom- 
plished Secretary of our Club. 
