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. Species from the Silurian 

 rocks have been described by Sir E. Murchison in his great work the 

 " Silurian System," by Professor McCoy in Sedgwick's Synopsis of the 

 Classification of British Palaeozoic Eocks," 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 Traj'>?4 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 refer- 

 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. 



CRissopoDiA EMBLETONiA § (Tate). Plate II. 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 ; cirri 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 Pliilosophical Society, vol. x. p. 181. 

 t The Natm-alist, Nos. 1. and XL pp. 14 and 41. 

 t Proceedings of the Yorkslni-e 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. 



