ANTHOZOA. 179 



irregularly arranged, varying from eight to fifteen in the space of 10 mm. Mural pores 

 comparatively large, circular, with distinctly elevated margins, disposed in one, two 

 and sometimes three ranges. Where one or two ranges occur the pores are regularly 

 arranged one above the other; where three ranges occur the disposition is more irregu- 

 lar."— Hall, 1887. 



Dimensions — Variation in size of coralla indicated by specimens figured. Range 

 in greatest internal diameter of corallites of the various specimens and maximum range 

 for any one specimen 0.8 to 3.5 mm. 



Remarks — The arrangement of the tabulae is accurately determinable on portions 

 of part of the specimens. The disposition of the mural pores is accurately determinable, 

 and the septal spines are observable (to the unaided eye) on portions of all of the speci- 

 mens. Epitheca is shown on all of the specimens. 



Genus Striatopora Hall 



Striatopora missouriensis Meek and Worthen? 

 Plate 42, figures 1-4 

 Striatopora missouriensis Meek and Worthen, 1868, 111. Geol. Surv., vol. Ill, pi. 369, 



pi. 7, fig. 4. 

 Striatopora missouriensis Keyes, 1894, Mo. Geol. Surv., vol. IV, pt. I, p. 121. 



Description — "Corallum slender, ramose; branches cylindrical; cells obliquely 

 ascending from an imaginary axis, rather distantly separated, slender and rounded with- 

 in, but enlarging and curving outwards to the surface, where they terminate in com- 

 paratively large, transversely oval, or subrhombic mouths, alternately arranged, and 

 directed more or less obliquely upwards, with a sharp, rather prominent lip below; 

 striae distinct, ascending from each cell, and continued up the upper side of the en- 

 larged opening, to the lower margins of the succeeding openings above. 



"Length unknown; diameter of an imperfect branch, about 0.20 inch." — Meek 

 and Worthen, 1868. 



Remarks — Meek and Worthen's figure of S. missouriensis is too poor to permit more 

 than doubtful reference of the material at hand to this species from the Helderbergian 

 of Missouri. The specimens might be assigned to S. issa Hall 1 . 



A description of the material at hand follows : Corallum ramose, composed of closely 

 united corallites (whose orifices are polygonal and unequal in diameter) which ascend 

 obliquely from axis, rapidly increase in size, and end obliquely upon surface. Calyces 

 funnel-shaped, sides marked by prominent longitidinal ridges that produce crenulation 

 of thin calyx-edges, walls pierced by comparatively large mural pores. 



Mean diameter of branches 6.5 to 15.0 mm. Range in greatest diameter of corallites 

 of the various specimens, and maximum range for any one specimen 1.0 to 4.0 mm. 



The specimens differ from S. betta Swartz in that the calyces narrow more rapidly 

 downward and the calyx-ridges are more prominent. 



Striatopora bella Swartz 

 Plate 42, figures 5-8 

 Striatopora bella Swartz, 1913, Md. Geol. Surv., L. Dev., p. 215, pi. XXV, figs. 1, 2. 



Description — "Corallum branching, dendroid, consisting of closely united prismatic 

 corallites which ascend along axis and then bend abruptly, terminating obliquely upon 

 surface; corallites quite unequal in diameter, more or less irregular in cross-section. 

 Calyx funnel-shaped, its base formed by a broad, flat tabula, its sides striated by twelve 

 low ridges, its edges thin and slightly crenulated by the termination of the ridges. 

 Walls of calyx perforated by large scattered pores. An occasional pore is seen to pierce 

 the tabulae in the single specimen observed. 



l 26th Ann. Rept. N. Y. State Mus. Nat. Hist., p. 114, 1874. 



