in the Totsdam Formation, 



2S5 



ones, they swell out opposite 

 to each transverse furrow, 

 thus giving to the side ridges 

 a beaded or knotted aspect, 

 each bead of the series 

 standing opposite a fur- 

 row. The highest part of 

 these lumps is about three 

 lines above the bottom of 

 the furrows, and about a 

 line and a half above the 

 surface on which the track 

 is impressed. 



Fig. 5, Uue-ntth nat. size 



My naturalist friends to whom T have exhibited the specimens, 

 appear disposed to consider the tracks those of some species of 

 gigantic mollusc, and I am given to understand there is now 

 living some small mollusc, whose track presents a series of 

 transverse ridges and furrows, without, however, the longitudinal 

 ones. From the resemblance of the track to a ladder, the name 

 proposed for it is Climactichnites Wilsoni^ the specific designa- 

 tion being given in compliment to its discoverer, Dr. Wilson. 



ARTICLE Xli.— Notes on the Coal Field of Pictou. By H. 

 PooLE, Esq., Superintendent of the Eraser Mine. 



(^Communicated to the Natural History Society by Principal Dawson.) 



[The facts contained in the following communication, may be 

 regarded as supplementary to those noticed in my Acadian Geo- 

 logy, and in a paper by Mr. Poole and myself, published in the 

 proceedings of the Geological Society. The coal measures of the 

 Albion mines, dipping to the N. E., at an angle of about 18^, 

 contain the great main seam, 36 feet in thickness, and 157 

 feet below this the deep seam, a bed of inferior but still great 

 thickness. To the north-west these coal measures are apparently 

 cut off by a great bed of conglomerate dipping north, beyond which 

 occur other coal measures, also with northerly dip. For rea- 



