COELENTERATA 



Class ANTHOZOA 



Order TETRACORALLA 



Family ZAPHRENTIDAE 



Genus STEREOLASMA Simpson 



Stereolasma rectum (Hall) 

 Plate VII, Fig. 1 



Fitromhodes (?) rectus Hall. 1843, Geol. N. Y., pt. iv, p. 209, fig. 5. 

 Streptelasma rectum Hall, 1876 (in part). 111. Devonian fossils, pi. xix, fig. 9. 

 Streptelasma rectum Grabau, 1899, Bull. Buffalo Soc. Nat. Sciences, vol. vi, 



p. 122, fig. 2. 

 Stereolasnia rectuvi Simpson, 1900, Bull. N. Y. State Mus., No. 39, p. 205. 

 Stereolasma rectum Clarke, 1903, N. Y. State Mus. Bull. 65, p. 55. 

 Streptelasma (Stereolasma) rectum Grabau and Shinier, 1906, N. Am. Index 



Fossils, vol. i, p. 56, figs. 78, 79. 



Description. — Corallum rather small, conical outline, rapidly tapering 

 toward the base; septa twisted near the center of the calyx forming a 

 central solid axis or pseudocolumella which projects prominently from 

 the bottom of the calj'x; dissepiments and tabiilae frequent; fossula well 

 marked : height, 3 or 4 cm., diameter of calyx, 1.5 to 2 cm. 



' The author desires gratefully to acknowledge the assistance given by 

 Dr. John M. Clarke and Professors Amadeus W. Grabau and Charles Schuchert 

 whom he has frequently consulted regarding the identification of imperfect 

 and doubtful specimens and those which are described as new species. He 

 also acknowledges the great assistance derived from the classic volumes of 

 New York Devonian Palaeontology in the descriptions of the species. Many of 

 those for the Brachiopoda, Pelecypoda, Gastropoda and Cephalopoda are modi- 

 fled from the well known and standard ones of that Nestor of American 

 Paleontology — Prof. James Hall — as published in volumes IV and V, parts 

 I and II, of the Palaeontology of New York; those for the Crustacea are 

 based in a similar manner upon the equally scholarly work by Hall and Clarke 

 in volume VII, while the characterization of the Corals in volume VI of the 

 Bulletin of the Buffalo Society of Natural Sciences by Prof. Grabau has been 

 drawn upon for the description of the Maryland specimens. 



C. S. P. 



