56 THE DEVONIAN OF MISSOURI. 



Genus Ceratopora Grabau 



Ceratopora grabaui n. sp. 



Plate 4, figures 2 and 3 ; plate 3, figure 5. 



Corallum maintaining about the same width with upward growth; tubules closely 

 aggregated, spreading in various directions so that the outer points of a cross-section 

 of a corallum lie in a rude circle. Corallites closely connected through their entire 

 length, maintaining about the same diameter. The diameter of the tubes is 13^ to 2 

 mm. No pores have been observed in the walls and no spines in the tubes. In some 

 cases the entire corallum bifurcates several tubes going with each branch, branches of 

 about the same size. Figure 3 of plate 4 shows such a branching. Figure 5 of plate 3 

 shows the central mass with the tubes broken away. 



Occurrence — Mineola limestone. of Montgomery and Ralls Counties. 



Ceratopora snyderensis n. sp. 

 Plate 3, figure 2 



Corallum simple, unattached excepting at the base. Corallites slightly curved 

 and gradually enlarging toward the circular aperture. In the two specimens on which 

 the description is based the first bud is given off 8 mm. from the base. The second bud 

 is 12 mm. higher than the first. The buds are almost at right angles to the main coral- 

 lite. Interior with circumferential cysts. Cysts few but of large size. Septal spines few, 

 of medium size. 



This species differs from Ceratopora jacksoni Grabau in its smaller size and lack of 

 longitudinal striations. 



Occurrence — Snyder Creek shale of Callaway County. 



Class HYDROZOA 



Subclass Hydromeciusae 



Family Stromatoporoidea 



Genus Stromatopora Goldfuss 



Stromatopora solidula Hall and Whitfield 

 Plate 4, figure 1; plate 5, figures 1-6. 

 1873. Stromatopora solidula Hall and Whitfield, 23d Ann. Rept. N. Y. State Cabinet 

 of Nat. History, p. 227, pi. 9, fig. 4. 



Hall and Whitfield's description — "Specimens in irregular masses, or incrusting 

 foreign substances, the form of which they frequently retain. Surface extremely irregu- 

 lar and more or less thickly covered with small conical or rounded irregularly disposed 

 pustules, giving origin to minute, indistinct, flexuous, ramifying channels, which traverse 

 their sides and the intervening spaces, seldom extending to any great distance. Vertical 

 section showing closely arranged horizontal layers of varying density, giving a strongly 

 lamellose appearance: the individual plates or vertical columns scarcely or not at all 

 distinguishable, but showing the ramifying tubes of different sizes very distinctly." 



Remarks — This is an exceedingly variable form frequently occurring in nodules 

 of various sizes and not uncommonly incrusting other forms. Over large surfaces there 

 may be no pustules while other surfaces may have pustules closely crowded. The sub- 

 stance is so dense that structure has not been satisfactorily determined in microscopic 

 sections. The peculiar ornamentation shown in the drawing is a conspicuous feature 

 of all good specimens. The slightly weathered specimens show no trace of them. 



Occurrence — Abundant near the bottom of the Snyder Creek shale in Callaway 

 County. Locations 1 and 2 are good collecting grounds. 



