120 



Scientific Intelligence. 



(5.) Crocodilus humilis, Leidy. — The species is founded on ten speci- 

 mens of shed crowns of teeth, apparently of a small species of crocodile. 

 The largest ' specimen is lines long and 3-J- lines in diameter at base, 

 which is nearly circular. Another specimen is 7 lines long and 2-J- lines 

 in diameter at base ; and a third specimen is 6 lines long and 3^ lines in 

 diameter at base. These are all moderately curved conical, nearly circu- 

 lar in transverse section, with the two usual internal acute ridges, and 

 with the intervening surfaces slightly striate or nearly smooth. The 

 crown of a posterior tooth is compressed, mammillary in form, 2-J lines 

 long and 2-J- wide at base, with the summit obtuse, and the sides finely 

 and longitudinally rugose. 



(6.) Trionyx foveatus, Leidy. — The species is founded on fragments 

 of several costal and sternal plates. The exterior surface of the costal 

 plates is covered with pits, excepting close to the margins ; and the pits 

 are small and round at the vertebral extremity, and gradually increase in 

 size outwardly and become antero-posteriorly oblong oval and reniform. 

 A vertebral fragment of a third or fourth costal plate, a little over an inch 

 in length, is 11 lines wide and 2 lines thick. Small fragments of the 

 sternal plates present an exterior surface covered with broken vermicular 

 ridges and tubercles separated by wide intervals. Fragments of a hy- 

 posternal plate are 3 lines in thickness. 



(7.) Lepidotus occidentalis, Leidy. — A species proposed on five spe- 

 cimens of thick lozenge-shaped scales, with the root prolonged in the 

 direction of the long diameter. The enamelled surface of the scales is 

 smooth and shining. The largest one has its sides about 4 lines long, 

 the smallest one about 2-J lines long. 



(8.) Lepidotus Haydeni, Leidy. — A species proposed on a single speci- 

 men of a thick oblong square scale, the long sides of which measure 5 

 lines, and the short sides 3^ lines. The root projects forward from one 

 of the long sides, and the enamelled surface of the scales is covered with 

 parallel square lines. 



This species is named in honor of Dr. Hayden, who collected the re- 

 mains characterized in this paper ; and which remains, I suspect, indicate 

 the existence of a formation like that of the Wealden of Europe. 



In the same number of the Proceedings of the Philadelphia Academy, 

 Dr. Leidy has described several new fossil Mammalia from Nebraska ; 

 two Pachyderms which he names Leptochoerus spectabilis and Hyracodon 

 nebrascensis ; a Ruminant, Leptauchenia decora ; a Herbivorous Cetacean, 

 Ischyrotherium antiquum ; four Rodents, Steneofiber nebrascensis, Ischy- 

 romys typus, Palceolagus Haydeni, Eumys elegans ; two Carnivores, 

 Amphicyon ? gracilis, and Deinictis felina. The Palasotherian remains 

 of Nebraska he refers all to his genus Titanotherium. 



4. Notice of a new Fossil Genus belonging to the Family Blastoidea, 

 from the Devonian strata near Louisville, Kentucky ; by B. F. Shumard, 

 M.D., and L. P. Yandell, M.D., (Ibid., p. 73.) — The remarkable Crinoid, 

 now for the first time brought to the notice of Palaeontologists, was dis- 

 covered by us as early as 1847, in a gray sub-crystalline limestone on 

 Bear Grass Creek, near Louisville, Kentucky, associated with characteris- 

 tic fossils of the Devonian system. At that time we had observed only 

 detached plates of the genus, which did not permit us to recognize its 



