REPORT OF THE STATE PALEONTOLOGIST 1902 



961 



The accompanying photographs, plates A and B, show the 

 eastern end of the track area at Bidswell's crossing as photo- 

 graphed by Mr P. P. Sharpies, in October 1902. Plate A is a 

 view looking southward across the better defined trails. The 

 point of the hunting knife rests at the end of one of the terminal 

 impressions into which the trails merge. Other similar oval 

 impressions are shown to the right and left. Plate B is another 

 view of the same surface looking southeast along the two dis- 

 tinct trails seen in the right hand side of plate A. 



The trails from Mooers agree in all essential characters with 

 the original description of Climactichnites. It is to be noted 

 that there are no traces of footprints and no medial furrow 

 which may be attributed to the dragging of a tail spine in any 

 portion of the trails which have been there studied. 



The size of the trails is quite uniform in breadth. Measure- 

 ments show them to vary between 5 and 6y 2 inches. The trans- 

 verse ridges which give rise to the ladder structure are spaced 

 about 1 inch apart, measured from crest to crest. 



Each of these transverse ridges passes on the margins into 

 the outside lateral ridges. Kegarding, for reasons shown 

 beyond, the terminal oval impression as in the direc- 

 tion toward which the animal was crawling in making 

 the trail, it may be stated that the transverse ridges 

 curve sharply forward at their margins to form the 

 lateral ridges. This is quite evident in some por- 

 tions of the trails, though it is not everywhere ob- 

 vious. In figure 1, this feature is diagrammatically 

 shown, together with the apparent overlapping of the 

 successive ridges at their margins. The median 

 ridge, in passing over which the transverse ridges 

 bend rather sharply forward, as seen in the photo- 

 graphs and in figure 1, is a sinuous line not uniformly 

 equidistant from the margins. Another important 

 characteristic of the Mooers trails is the distinct 

 pressing down of the sands in the making of the trail. 

 By whatever process the transverse ridges were made, they 

 were passed over and pressed on in the making. 



The above cited observations warrant, it appears to me, cer- 

 tain conclusions. 



Fig. 1. 

 Sketch of 

 sedentary 

 impres- 

 sion 



