Sternberg, C. H., 1922.

Explorations of the Permian of Texas and the chalk of Kansas, 1918.

Kansas Academy of Science, Transactions  30(1):119-120.

Copyright © 2002-2013 by Mike Everhart

Created 08/28//2002 -Last updated 02/17/2013

LEFT: The specimen of Tylosaurus proriger (USNM 8898) found by George Sternberg in 1918; On exhibit in the United States National Museum (Smithsonian).

Although Sternberg published the discovery, it was more or less lost in history until I came across the report in his two page note in the Transactions of the Kansas Academy of Science (1922):

“…I joined them in the Kansas chalk in Logan county, on Butte creek. I was so fortunate as to find a fine tylosaur skeleton the second day in the field. There were twenty-one feet of the skeleton present in fine chalk. The complete skull was crushed laterally. Nearly the complete front arches and limbs were present, as was also the pelvic bones and both femora. All the vertebrae to well into the caudal region beyond the lateral spines were continuous, with the ribs in the dorsal region. Between the ribs was a large part of a huge plesiosaur with many half-digested bones, including the large humeri part of the coracoscapula, phalanges, vertebrae, and, strangest of all, the stomach stones, showing that this huge tylosaur, that was about twenty-nine feet long, had swallowed this plesiosaur in large enough chunks to include the stomach. How powerful the gastric juice that could dissolve these big bones! This specimen I sent to the United States National Museum.”

                                                                        Kansas Academy of Science.                                                         119

Explorations of the Permian of Texas and the Chalk of

Kansas, 1918.

CHARLES H. STERNBERG.

     The splendid skeleton of Dimetrodon gigas I collected in 1917 and sold to the United States National Museum has been mounted at last, and is one of the world's famous specimens. I do not know of a more perfect single individual. It came from the famous Craddock quarry discovered by the late Doctor Williston's assistant, Mr. Miller. Through the kindness of Mr. Craddock, the owner of the quarry, I not only collected there in 1917, but last year. Owing to the fact that the quarry is now covered with about twenty feet of earth and clay of the toughest character the work was very difficult and I was obliged to employ a man with a heavy team of horses, with plow and scraper. I succeeded in securing many more or less perfect skeletons of several species. Unfortunately, none were as perfect and capable of making into a fine open mount as the National Museum specimen. This quarry is in the face of a hill. As I have gone deeper and deeper into the hill the manner in which the animals were stranded here becomes more and more apparent. On the very bottom of the quarry are innumerable bones of very small animals, Seymoriana and other batracians, etc. They are usually scattered and are free from matrix, consequently they are among the rarest of Permian vertebrates that have not been injured by the encrusting silica that covers all the other bones at higher levels, and which is so difficult. to remove. The National Museum specimen came from near this level. Above are about four or, five feet in the heavy, fine-jointed red clay. Though water has filtered and coated all the bones with silica, I found several more or less perfect skeletons. Often the entire column, except the tail, with enormous spines were present; sometimes the arches and limbs, as in the best specimen we found, discovered by my son, George F.  The longest spine of this individual was four feet. Most of the column and tail were present. The skull was disarticulated. The arches seemed present. Many of the spines, however, were twisted and interwoven, all the bones covered with a thin coating of silica. As I understood Doctor Gilmore, it took two preparators a year to prepare and mount the National Museum specimen. You will realize something of the labor it will take to prepare this one. This, with my whole collection from the Craddock quarry, I sold to the American Museum.

     From Seymour, Tex., my boys, George and Levi, drove my car to the Rock creek Horse quarry, near Tulia, Tex.. but the formidable mass of sand that lay above it induced them to turn their Ford truck northward, and I joined them in the Kansas chalk in Logon county, on Butte creek. I was so fortunate as to find a fine tylosaur skeleton the second day in the field. There were twenty-one feet of the skeleton present in fine chalk. The complete skull was crushed laterally, nearly the complete front arches and limbs were present, as was also the pelvic bones and both femora. All the vertebræ to well into the caudal region beyond the lateral spines were continuous, with the ribs in the dorsal region. Between the ribs was a large part of a huge plesiosaur with many half-digested bones, including the large humeri, part of the

coracoscapula, phalanges, vertebræ, and, strangest of all, the stomach stones, showing that this huge tylosaur, that was about twenty-nine feet long, had swallowed this plesiosaur in large enough chunks to include the stomach. How powerful the gastric juice that could dissolve these big bones! This specimen I sent to the United States National Museum. A little Clidastes skeleton found by my son Levi proves not only to be new, but possessed of remarkable characters not yet described. I will only in a general way give you an idea of this little sea lizard. It is 8 ½ feet long, skull 14 inches long. Levi in preparing the skeleton restored the maxilla, jugals, nasals and prosquamosals, with the ends of some of the teeth; also four of the cervical and one dorsal vertebra. These had been destroyed by incrusting gypsum. The bifrucated coracoids, 2 inches wide, are large compared to the scapulæ, which are only 1 ¼ inches wide. The most remarkable thing about this mosasaur is the fact that the humeri and femora have distinct, round heads, similar to those of mammals. Further, all the Clidastes humeri I know are broad, square bones, nearly as broad as they are long. In this specimen the humerus is 2 ¼ inches, while it is only 1 ¼ inches wide in the widest part; the same with the femur. The front paddle is 7 inches long to ends of first row of phalanges; width only 2 ½ inches. The column is continuous to the pygals, where they are scattered. The pelvic arches and paddles are only partially preserved. The caudals are beautifully preserved, with a high fin in the last half of the column; the chevron well preserved, with all of them anchylosed to the centra of the vertebræ. The only genus among the mosasaurs where this is the case. They usually are distinct, the proximal heads fitted snugly into little basins hewn out., as it were, from the centra of the vertebræ. I own this new Clidastes. [now Eonatator (Halisaurus) sternbergi, described by Carl Wiman, 1920; revised to Halisaurus by Russell (1967) and most recently to Eonatator (novem gen.) by Bardet, et al., 2005).

    We secured two specimens of Platecarpus coryphæus of exactly the same size. One found by Levi Sternberg has much of the head, the column, and ribs to the pygals. The second, found by George F. Sternberg, has a very complete tail to the very end, and the pelvic arch and one paddle; other specimens furnished the rest of the paddles. We have mounted this as a slab specimen, and makes a skeleton 17 feet long-very impressive, indeed. George F. Sternberg found also a very fine skull and most of the skeleton of a small Pteranodon. The skull is only 27 inches long; missing, only the crest and front of the mandibles. Both coracoscapula are present, with one humerus, radius, ulna, carpal joint., and most of one elongated finger. Both hind limbs and several vertebræ and ribs. This, when prepared, will be one of the few fine skulls of these flying reptiles. We secured also a very fine Portheus, complete, nearly, except the ends of the ribs, the dorsal and caudal fins, and 18 caudal vertebræ. These we have restored, and we have a fish 13 feet long, with spread of tail fins of 35 inches. These are the chief discoveries of my last season's labor in the Permian of Texas and the chalk of Kansas.