189 



are from the Red River group of my section of the cretaceous rocks 

 of Texas. (Trans. Acad. Science, St. Louis, vol. i. p. 583.J 



They were collected by Dr. George G. Shumard, assisted by A. R. 

 Roessler, chiefly from the bluffs bordering Red River. The fossils 

 from Navarro come from an interesting series of beds not hitherto 

 recognised in Texas. Most of them were obtained from Septarias, 

 imbedded in blue and gray arenaceous clays. We have found more 

 than fifty species of fossils in these strata, a large proportion of them 

 new to science, and now for the first time described. Others corre- 

 spond with species described by Mr. Conrad from the Ripley Group of 

 Tippah County, Mississippi, and Eupaula, Alabama. I have been 

 able to recognise the following species common to the Tippah and 

 Navarro beds : Nautilus DeJcayi, BacuUtes Tippaeiisis, B. Spillmani, 

 Purpura canceUaria, Rapa supraplicata, Stromhus densatus, Ficus suh- 

 densatus, Pleuroioma Ripleyana, Plioladomya Tippana, P. elegantula, 

 Cardium Spillmani, Legumen elliptica, Sdiquaria hiplicata, Pecten sim- 

 plicius, P. Burlingtonensis, and Exogyra costata. 



It is somewhat remarkable that although several species of Cepha- 

 lopoda, belonging to the Genera Nautilus, Ptychoceras, Helicoceras, 

 Turrilites, and Baculites have been found in the Navarro beds, not a 

 single species of Ammonites or Scaphites has been met with. 



The precise stratigraphical relations of the Navarro beds, with 

 reference to the other members of the cretaceous in Texas, have not 

 been certainly determined, though I am inclined to believe their 

 position is above the Austin limestone of the Texas section. 



St. Louis, Mo., August 12, 1861. 



CEPHALOPODA. 

 Genus Scaphites, Parkinson. 



S. VERRUCOSUS, (n. sp.) Shell of medium size, short, subovate, 

 volutions sh'ghtly embracing ; last volution enlarging somewhat 

 rapidly towards the aperture, produced horizontally for a distance 

 equal to one fourth the entire length of the shell, and then turned 

 suddenly upwards and backwards so as to bring the aperture near 

 the spire ; sides and dorsum strongly rounded ; aperture wider than 

 high, apparently' semi-elliptical ; surface of body volution studded 

 with small nodes, with circular bases, and arranged in three or fom' 

 revolving rows on either side ; also marked with small moderately 

 distinct rounded costae, some of which pass entirely across the volu- 

 tion, and others becoming obsolete at the nodes. The ribs are 

 scarcely as wide as the intervening spaces. 



Sept£8 with slender branches ; dorsal lobe about as long but not as 

 wide as the superior lateral, having four branches on either side, the 

 basal ones simple, those next above with two, and the third from base 



