58 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.46. 



Camarocrinus (Lololithus) is found associated with calices of the 

 crinoid ScypJiocrinus, and in 1900, Dr. F. A. Bather definitely asso- 

 ciated these two genera as parts of one and the same organism. 



No association of Camarocrinus and Scypliocrinus in America had 

 ever been noted, although the Camarocrinus occurred frequently in such 

 large numbers as to make up entire limestone layers. In Oklahoma, 

 where these layers sometimes outcrop at the surface, cobblestone- 

 Hke masses ■ frequently strew the ground in great profusion. Since 

 1904 Mr. Springer has directed his efforts toward the discovery of 

 new evidence upon Camarocrinus, with the result, as announced at 

 the 1912 meetmg of the Paleontological Society in New Haven, 

 Connecticut, that he is now able to show, fu"st, that the genus Scy- 

 'pJiocrinus occurs at several horizons in the late Silurian and early 

 Devonian of America; second, that the Camarocrinus bulbs are fre- 

 quently connected at the distal end of the stem with crinoids 

 belongmg to the genus ScypJiocrinus; and thu'd, that these bulbs 

 usually occur with the stalk end upward and not downward as 

 before supposed. Mr. Springer will publish the evidence for these 

 conclusions later, but a few notes regarding the slab which is the 

 subject of the present' article are in order. 



Durmg the summer of 1904, as recorded in Schuchert's paper, the 

 present writer observed Camarocrinus m the bluffs along the Missis- 

 sippi Kiver a few miles north of Cape Girardeau, Missouri, in the 

 outcropping edge of a layer with numerous large crinoid stems. In 

 1911 Dr. E. O. Ulrich found a detached mass of crinoidal limestone 

 from the same layer in which was embedded the well-preserved calyx 

 of a large ScypJiocrinus. These discoveries were so promising of 

 favorable results that Mr. Sprmger asked his private collector, 

 Mr. Frederick Braun, to carefully examine this general area m the 

 hope of findmg the f ossiliferous bed at some place sufficiently exposed 

 for careful collectmg. After a protracted search along the bluffs 

 facing the Mississippi River, Mr. Braun finally succeeded in locating 

 the crmoidal layer at a point where he could carry on quarrying 

 operations. Here several weeks' work resulted not only m some 

 most remarkable specimens of crinoid, but in settlmg finally the 

 facts upon which the mterpretation of Camarocrinus must depend. 

 The work was of no small difficulty, as the physical obstacles were 

 formidable. The layer could be readily traced but it was not every- 

 where fossilif erous, and as the crinoids occurred only on the lower side 

 a place had to be found where there was a soft seam underneath along 

 which the fossiliferous stratum would readily separate from the one 

 next below. The fossiliferous part of the layer proved to be limited 

 to a smaU area which contained the remains of a thickly crowded 

 crinoid colony suddenly killed by some change in the water and 

 embedded in the soft muddy sea bottom mthout material disturbance 

 by currents. 



