observable in the Sdndsione Strata of Sussex. 241 



When a large surface is first exposed, a most interesting ap- 

 pearance is presented, and the spectator is struck with the con- 

 viction that he is standing on an ancient shore. In some places 

 the furro\vS are deep, affording evidence of the water having 

 been much agitated, and the ripple strong ; in other instances 

 the undulations are gentle, and are frequently intersected by 

 cross ripples, from a change in the direction of the waves. On 

 some parts of the stone there are slightly elevated longitudinal 

 ridges of sand, made up of gentle risings, disposed in a crescent- 

 like form, resembling most closely the sand ridges which are 

 produced by the little rills which flow back into the sea or 

 river at low water. Some of tlie slabs are covered with thin 

 angular ridges, irregularly crossing each other like the fissures 

 in septaria, and which have obviously been caused by the depo- 

 sition of sand into the crevices made in sand or mud by drying. 

 A very considerable portion of the stone (the flat as well as the 

 furrowed variety) is covered with small cylindrical bodies, which 

 have been moulded in the hollows pi'oduced by some species of 

 vermes. Similar forms of a larger size also occur ; these re- 

 resemble the trails left by mussels, and have probably been oc- 

 casioned by some of the analogous bivalves whose remains are 

 imbedded in the strata of Tilgate Forest *. 



Since, in some instances, the foot-marks of animals (supposed 

 to be reptiles) have been discovered in sandstone of England 

 and Scotland, we examined the slabs in the quarries at Horsham 

 with considerable attention, in the expectation that similar in- 

 dications might there occur ; but although our researches were 

 not attended with success, yet as reptiles are known to have 

 existed in vast numbers on the land and in the water at the 

 period of the formation of these strata, and as the markings on 

 the surface of the stone is a proof that it was deposited in shal- 

 low water, and was occasionally left dry, it is more than pro- 

 bable that impressions will sooner or later be discovered. The 

 oljject of this brief memoir is to draw attention to the subject, 

 in the hope that persons of taste and leisure will pursue the 

 inquiry. 



• This appearance is common in the sandstone quarries around Edinburgh. 



