1 8 Cincinnati Society of Natural History. 



little pressed together and somewhat weatherworn ; interior de- 

 stroyed. Measures seven ;///;/. in diameter. 



Collected by Mr. Geo. Ashman, in the Cincinnati Group 

 near Transit Ohio, about 400 feet above Low water mark in the 

 Ohio River. 



CVRTOCERAS TENUISEPTUM, nOV Sp. 



Plate I. Figs. 3 a-b-c. 



Specimen medium size, with slight curvature and tapering 

 very slightly. Composed of twenty thin septa, equal in width and 

 rather circular in section. Siphuncle small and dorsal. Specimen 

 is thirty two tniii. in length, and measures in section seventeen //////. 

 in its greater, and fifteen mm. in its lesser diameter. 



3a is a dorsal view of a larger specimen of the same species, 

 having five septa and a body- chamber showing the sinus. The 

 body chamber is 27 //////. in lergth, and measures in section 23 ww. 

 in its greater, and 20 mm. in its lesser diameter. This specimen 

 has a thick shell, but shows no external markings. It also shows 

 that a coral had begun its growth in the body-chamber and ex 

 tended somewhat beyond it. This species has about seventeen 

 septa to an inch. 3a is a remarkable specimen, as it is the only 

 one figured and known to me of this group with a complete body- 

 chamber. 



Collected by the author in the Cincinnati Group near Waynes- 

 ville, O., and at Versailles, Ind. 



In the 35th Report of the N. Y. State Museum, Mr. C. D. 

 Walcott describes two species under the genus of Merocrinus. As 

 a specimen which I have proves to belong to this genus, and is 

 the same species which Mr. Ulrich has described and figured in 

 Vol. II., Plate 7, figure 14 of this Journal as Dettdrocrinus ciirtis, 

 with a question as to the genus, I therefore figure the specimen to 

 give a better idea of it and place it under the genus Merocrinu.s. 

 Below is the description of the genus as given by Mr. Walcott : 



"MEROCRINUS.— Waixott. 



"General appearance of the body not unlike that of some 

 species of Hcterocriuus and Deudrocrinus. 



"Underbasals pentangular, low and broad in the typical spe- 

 cies. Basals hexagonal; radials pentagonal. Brachials six to seven 

 in each ray, the upper plate pentagonal and supporting the free 

 divisions of the arms above. In the right posterior ray there is a 



