LMATTHKW] REMARKABLE FORMS OF THE LITTLE RIVER GROUP 123 



Straddle (width between the footprints), average, 8 mm.; the 

 nearest approach is about 5 mm., and they sometimes separate to a dis- 

 tance of 10 mm. 



Stride (space between the footmarks in line) of the right side 5 

 mm., of the left side 6 mm., for a part of the track. 



The individual footmarks of the right side are about 3 mm. broad ; 

 those of the left side vary from 4 mm. to 7 mm. 



Horizon and Locality. — Dark gray sandy shale of the Lower Cor- 

 daite division, at Barrack Point, St. John. Collected by A. G. Leavitt. 



To judge by the duplicate impressions of the feet of the left row the 

 animal that made them may have been an insect, perhaps apterous, 

 though a Meristome or an Arachnid may have made similar impressions. 



AcRiPES MINOR n. sp. Plate I, Figs. 4 and 5. 



This is a narrower track than that of A. incertipes, but shows the 

 same type of footprints. In some cases these are punctiform, but they 

 often show an elongated impression of a claw or point; as in the species 

 above named we assume that the points are directed forward. The last 

 part tof the track shows much uncertainty in the placing of the foot- 

 prints of the right side ; further back, on this side, we see a duplication 

 of the footmarks in threes, in both cases the inner set of footprints are 

 elongated, while those of the main track here are punctiform. Beyond 

 a bend in the track there is a duplication of the footmarks on the left 

 side, and further on a doubling of those of the right. 



Stride, 4-5 mm. Straddle, about 15 mm. 



Horizon and Locality. — Lower Cordaite shales at Barrack Shore, 

 St. John City. Collected by A. G. Leavitt, 1809. 



AcRiPES Leavitti n. sp. Plate III, Figs. 3 and 4. 



A small species showing a more regular track than the others. The 

 footprints observed are punctiform and mostly nearly circular. In one 

 example of the mould some are rather oval, one track has a jog in the 

 series of footprints near the beginning. The creature had the habit of 

 stepping in its tracks, though in some cases the two impressions are 

 separated and the prints thus become twice as numerous. At one place 

 on the right side of another specimen the footprints are doubled, there 

 being three faint, elongate ones outside of the regular track. 



Stride, 3 mm. Straddle, 8 mm. 



Horizon and Locality. — Lower Cordaite Shale at Barrack Shore, 

 St. John. Collected by A. G. Leavitt, 1809. 



