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Show 217 them equal, if not superior, to anything before found in Europe or America. Professor Cope, in the work above quoted, has made a list of all the genera and species now known in the Cretaceous, which shows fifty- one hitherto described, of which Europe furnishes but four, and Kansas twenty- six. To this number must be added six or eight which hare been discovered by our party within two years, which are now in possession of Professor Marsh, who will soon publish a technical description of them. New Jersey comes next, furnishing fifteen species. Although this formation extends quite widely into Nebraska, but few vertebrates have been found within that State. They have been collected most abundantly in the Saline and Smoky Hill Valleys, and nearly all from the Niobrara proper, above the massive limestone of the Fort Hays division. It must be recollected that this deposit is never over 200 feet in thickness. The Sanrians are of all sizes. One from Jewell County was about 70 feet long, while two species were only 6 feet. Most frequently they vere from 25 to 40. The specimens are frequently represented by a few bones washed out and lying exposed. But the best are obtained by finding a projecting fragment, and then following the skeleton into the compact shale or chalk. This sometimes requires much hard labor, but is the most satisfactory, as the fossils are, in such cases, in a better state of preservation. A single specimen has cost us as much as six days' labor. As tbe bones were sometimes friable, sketches of the best specimens were made before removal. The fossilizing material is lime combined with a little silica. Coprolites of fish and Saurians are frequently found, containing the remains of the food of the animal. Small fish appeared to be the most common food j but in one instance a rare crustacean was found preserved in this way. The coprolites are not so hard as those of Europe, being little firmer thau chalk, and finer- grained. The following analysis of a Sauriau coprolite from Wallace County is by George E. Patrick, professor of chemistry in the University of Kansas: Moisture 1.22 Organic matter 42 Oxide of iron and alumina 29.99 Lime 24.31 Alkalies, small amount, undetermined. Silica ( combined) 19 Phosphoric acid 34.88 Carbonic acid 7.05 Snlphuric acid 1.92 99.98 In some cases, the undigested organic matter ( bones) was one- fourth of the whole weight. From this deposit, Professor Marsh hasdescribed three species of Pterodactyls, new to science, and Professor Cope one. But as the specimens were not perfect, and two are quite similar, it may be concluded that they are identical. One of a new genus was recently found by me, and is in the hands of Frofessor Marsh. Those from Kansas vary from the European species in their great size, the largest foreign being but little over 10 feet in extent pf wing, while the smallest of those from the Niobrara is 15 feet and the largest are fully 25 feet. Fragments of the boues are frequent, but usually in poor preservation, in strong contrast, in this respect, with the other vertebrate remains. The long bones, being very hollow, were compressed to the thickness of one-tenth of an inch, and exceedingly friable. The articulations, being |