3*22 THE CANADIAN NATURALIST. [Jan. 



rally. They are described in Sir W. E. Logan's Report on the 



Geology of Canada, 1863, at p. 32. 



The impressions referred to consist of perforations approaching 

 to a cylindrical form, and filled with rounded siliceous sand, more 

 or less stained with carbonaceous and ferruginous matter, more 

 especially near the circumference of the cylinders. These super- 

 ficial portions being harder than the containing rock, and of darker 

 colour, and also harder than the interior of the cylinders, project 

 as black rings from the weathered surfaces ; but in their continua- 

 tion into the interior of the mass, they appear only as spots or 

 lines of a slightly darker colour, or stained with iron-rust. 



When sliced transversely and examined under the microscope, 

 they appear as round, oval, or semicircular holes drilled through 

 the rock, and lined around their circumference with dense and 

 dark-coloured siliceous matter, while the axis, which is often of a 

 bilobate form, is comparatively transparent and of softer texture. 

 The perforations are often at right angles to the bedding, but in 

 some cases nearly parallel with it. 



In regard to the origin of these perforations, I suppose that they 

 may have been either (1) burrows of worms filled with sand sub- 

 sequently hardened and stained at the surface, or (2) tubes com- 

 posed of sand, like those of Sabella, or (3) cavities left by the 

 decay of Alga3 and filled with sand. The first I think the most 

 probable view. 



I may add that the beds at Madoc, containing these supposed 

 fossils, hold also, on their weathered surfaces, impressions with rude 

 casts of concentric laminae like those of Stromapotora or Eozoon, 

 but too obscure for determination. The limestones interstratified 

 with these beds also contain fragments of Eozoon not fossilized 

 by serpentine but simply by carbonate of lime, carbonaceous 

 fibres, spicules like those of sponges, and lenticular bodies of un- 

 known nature. - Journal of the Geological Society of London. 



OBITUARY. 

 The Right Honourable Sir EDMUND HEAD, Bart., K.C.B., 

 L.L.D., F.R.S., etc. 

 By the sudden death of the able and patriotic man whose name 

 stands at the head of this article, Canada loses one of the few states- 

 men in the mother country interested in her welfare, and having 

 influence to make their o;o:>d wishes effectual. Sir Edmund, after 



