Prof. Hitchcock on Ichnolithology, or Fossil Footmarks. 303 



Before the London Geological Society in November, 1842, 

 Mr. H. E. Strickland gave an account of certain impressions 

 upon the lias bone bed in Gloucestershire, which, in his opinion, 

 were made by fish, or invertebrate animals. The straight grooves 

 and small pits, he thinks, may have been formed by fish, 

 striking against the bottom, or probing the mud for food with 

 its nose. The curved grooves he refers to an acephalous mol- 

 lusk, the Pullustra arenicola, and certain tortuous tracks to an- 

 nelidous worms'.* 



In June, 1843, Dr. Buckland gave an account before the Lon- 

 don Geological Society of certain " Ichtliyopodolites, or petrified 

 trackways of ambulatory fishes upon sandstone of the coal for- 

 mation," in Flintshire, England. They consist of curvilinear 

 scratches disposed symmetrically at regular intervals on each side 

 of a level space about two inches wide, which in his opinion 

 may represent the body of a fish, to the pectoral rays of which 

 animal he attributes the scratches. They follow one another in 

 nearly equidistant rows of three scratches in a row, and at inter- 

 vals of about two inches from the point of each individual scratch 

 to the points of those next succeeding and preceding it.f 



In this country two new localities of tracks have been dis- 

 covered of late, which are of no small interest. In rocks of the 

 carboniferous series in Nova Scotia, Mr. Logan has found tracks 

 of a reptile of unknown species. This is the first example, I 

 believe, of tracks below the new red sandstone ; and, indeed, I 

 am not aware that we have had any previous evidence of the 

 existence of reptiles as low as the carboniferous group.J 



Our associate, W. C. Redfield, Esq., has during the last year 

 discovered the Ornithoidichnites tuherosus in the new red sand- 

 stone of New Jersey, in connection with fossil fish. The speci- 

 men which he showed me is of the most decided character, and 

 inspires the hope that other developments in regard to tracks may 

 be expected from the red sandstone scries extending through 

 New Jersey, Pennsylvania, Maryland, Virginia, and North Car- 

 olina. <§> 



* Lond. Ed. and Dub. Phil. Mag. for Jan. 1844, Supplement, p. 531. 



t Philos. Mag. for March, 3844, p. 230. 



\ Am. Journal of Science, Vol. XLv, p. 358. 



§ Ibid. Vol. XLV, p. 134. 



