Expeditions in the Texas Permian 235 



transverse projections, which terminate in rounded 

 knobs, were all broken in situ, and were also flexed 

 and tilted with the strata, so that great care was 

 necessary in following them. They were about 

 three inches apart. I numbered the spines i, 2, 3, 

 etc., not with reference to their natural position, but 

 to the order in which I came to them. A good 

 many of the rounded ends of the lateral spines were 

 missing, having been washed down the slope. I 

 hoped to find them later. 



As I studied these remarkable spines, many of 

 them, near the center of the body, three feet high, 

 with the lateral spines alternating or opposite, I in- 

 stinctively called the creature the ladder-spined rep- 

 tile ; and I cannot see how Professor Cope could have 

 imagined that these spines had any resemblance to 

 the mast and yard-arms of a vessel, and that there 

 was a thin membrane stretched between them which 

 caught the breeze and acted as a sail. Later dis- 

 coveries show it to be a land animal. Professor 

 Osborn's magnificent restoration of the Naosaurus 

 is shown. (Fig. 33.) 



As I have said, it was a long and trying task to 

 take up the skeleton, as it was in thousands of frag- 

 ments. If I had dug them up as one would dig 

 potatoes, no one would ever have had the patience 

 to put them together again. So I took up each 

 spine in sections, wrapping say fifty fragments to- 



