58 ICHNOGRAPHS OF THE 



Fig. 3. Acanthichnus tardigradus, from a specimen in the possession of Am- 

 herst College. 



Fig. 4. (?). From a specimen in the collection of Amherst College. 



Fig. 5. Hexapodichnus magnns; specimen in the collection of Roswell Field. 



PLATE XLI. 



Fig. 1. Lithographus hieroglyphicus, from a specimen in the collection of 

 Roswell Field. 



Fig. 2. Bifurculapea tuberculatus, from specimen in collection of Roswell Field. 



Fig. 3. Conopsoides larvalis, from specimen in the collection of Roswell Field. 



Fig. 4. Bif n rcnla pes. from specimen in the possession of Wm. Chirk, of St. Louis. 



Figs. 5 and 6. Bifurculapea laqueatus. Both these figures, taken from dif- 

 ferent parts of one stone, in the possession of Roswell Field. 



PLATE XLII. 



Fig. 1. The stone from which this figure was lithographed is in the collection of 

 the late Dr. J. C. Warren, of Boston. 



Fig. 2. A part of the stone having this track is in the possession of Roswell Field. 

 Fig. 3. (?). 



PLATE XLIII. 



The impression here photographed is one of anomalous character, and Dr. Deane 

 thought it impossible to decipher it. 



Dr. Hitchcock thinks it the imprint of some species of fish, to which he gives the 

 name of Ptilichnus anomalus. 



The Plate represents the impression the size of the original. 



