May, 1U17| Silurian Fossils from Ohio 239 



The specimen here described differs from both Callocystites 

 jeivetti, Hall and Callocystites canadensis, Billings, from the 

 Rochester shale, in its globular rather than olive-shaped form, 

 and in its granulose rather than deeply pitted surface. 



No comparison with the type of Ilemicosmites subglobosiis, 

 Hall (Twentieth Report, New York State Mus. Nat. Hist., 

 pi. 12, fig. 13, 1868) is possible, for me, since, after repeated 

 attempts, I am unable to orient this type so as to identify the 

 plates. It is evident that the description of the species pub- 

 lished by Hall was not based on this type, but upon material 

 similar to that used by Schuchert in his description of Coelocystis 

 subglobosiis. 



The specimen diagrammed by Schuchert as a typical spec- 

 imen of Coelocystis subglobosiis agrees so closely with the plate 

 diagram of Callocystites jewetti that I am unable to determine 

 upon what features the generic distinction is to rest, unless it 

 be the small size and considerable distance between the discreet 

 halves of the pectinirhombs and the slightly different position 

 and form of plate 24 and of the immediately adjacent deltoids. 

 Since only the internal casts of Hemicosmites subglobosiis, Hall, 

 and Coelocystis subglobosiis, Schuchert, are known, further 

 comparisons are impossible at present. 



Lampterocrinus inflatus-minor, var. nov. Plate X, Figs. 2A, B. 



1868. Lampterocrinus inflatus. Hall, 20th Rep. New York State Cab. Nat. Hist., 



p. 328, pi. 10, fig. 6. 

 1900. Lampterocrinus inflatus, Weller, Bull. Chicago Acad. Sci., Nat. Hist. 



Surv., 4, pt. 1, p. 81, figs. 2, 3. 



General shape of the calyx as in Lampterocrinus inflatus, apparently 

 with similar pendant, laterally compressed, tubular arms. Ventral 

 disk greatly inflated posteriorly, but the center of radiation of the 

 ambtilacra appears to be more nearly central. Height of caljTC 22 

 millimeters, of which the tegmen forms a little more than a third. 



Infrabasals, basals, and radials and first costals as in Lampterocrinus 

 inflatus. The median part of the second costals curves strongly outward 

 and forms part of the lower side of the pendant arms. The second 

 costals evidently are followed directly by the distichals. Interbrachials 

 apparently as in Lampterocrinus inflatus. First anal plate larger than 

 the first plate in the interbrachial areas, higher than wide, followed by 

 three plates of which the middle one is conspicuously longer. The upper 

 half of this middle plate is surrounded by a semicircular series of five 

 plates, of which the end plates reach about the same level as the top 

 of that middle plate which the five plates in question .surround. 



