324 Geological Sociefi/. 



deviation from a straight line in any tliree successive prints ; and his 

 attention having been called to indications of joints in the ditlVrent 

 toes, he afterwards clearly recognised similar markings in tlie recent 

 steps of coots and other birds on the sands of the shores of Massa- 

 chusetts. Prof, Hitchcock has shown, that the same impression ex- 

 tends through several laminae, decreasing in distinctness in propor- 

 tion as the layer recedes from that in which it is most strongly marked, 

 or in proportion as the sediment filled up the hollows and restored 

 the surface to a level ; and Mr. Lyell states, that he has observed a 

 great number of instances of this fact. 



He also says, that he can scarcely doubt that some of the impres- 

 sions on the red sandstone of Connecticut are not referable to birds, 

 but he believes that the gigantic ones described by I'rof. Hitchcock 

 are Ornithichnites. At Smith's Ferry they are so numerous that 

 a bed of shale many yards square is trodden into a most irregular 

 and jagged surface, so that there is not a trace of a distinct footstep ; 

 but on withdrawing from this area to spots where the same tracts are 

 fewer, the observer, Mr. Lyell says, is forced to admit that the effect 

 in each case has been produced by this cause. 



On examining the shores on some small islands about fifteen miles 

 south-east from Savannah, the author was struck with the number as 

 vvell as the clearness of the tracks of raccoons and opossums imprinted 

 in the mud during the four preceding hours, or after the tide had be- 

 gun to ebb. At one spot, where the raccoons had been attracted by 

 the oysters, the impressions were as confused as when a tlock of 

 sheep has passed over a muddy road ; and in consequence of a gentle 

 breeze blowing parallel to the line of cliffs composed of quartzose 

 sand, the tracks had in many places already become half-filled with 

 blown sand, and in others were entirely obliterated ; so that if the 

 coast should subside, the consolidation of this sand would afford 

 casts analogous to those of Storeton Hill in Cheshire, yet the im- 

 pressions had been made and filled in a few hours. 



When considering the broad question whether the fossil foot-prints 

 were made by creatures walking on mud or sand after the ebbing of 

 the tide, Mr. Lyell reminds his readers of the fact that in the United 

 States, as in Saxony and Cheshire, the tracks in sandstone and shale 

 are accompanied by littoral appearances, as ripple-marks, the casts 

 of cracks in the clay, and often by the marks of rain. 



In regard to the age of the red sandstone of the valley of the 

 Connecticut and New Jersey, the author states he has nothing 

 to add to what had been previously advanced, by which its position 

 had been shown to be between the carboniferous and cretaceous 

 series. In the neighbourhood of Durham, Connecticut, he had col- 

 lected in the sandstone, fishes of the genera Palseoniscus and Cato- 

 pterus, but no other organic remains, except fossil wood. 



In conclusion, Mr. Lyell remarks, 1st, that the Ornithichnites of 

 Connecticut should teach extreme caution in inferring the non- 

 existence of land animals from the absence of their remains in con- 

 temporaneous marine strata ; 2ndly, that when this red sandstone of 

 Connecticut was deposited, there was land in the immediate vici- 

 nity of the places where the Ornithichnites occur ; and that but for 



