1 20 



Cincinnati Society of Natural History. 



spaces occupied by small pores: coraliites arising from a delicate, 

 striated epitheca ; calices sub-oval or sub-circular : walls thin, but 

 thicker on one side than on the other : tubes slightly curved at the 

 base, then vertical to the surface, sub-oval or sub circular : obscure 

 horizontal tabulae, with a few vesicular attachments to the walls. 

 (Jour. Cin. Soc. Nat. Hist., vol. 7, 1884, p. 21.) {Dia??iesopo?-a 

 owem Ulrich, Geol. Sur. Illinois, vol. 8, 1890, p. 467.) 



84. — M. (Fistulipora) rustica Ulrich (sp.) 1893. 



Corallum irregularly ramose, branches 5 to 10 mm. in diameter: 

 surface with low, rounded eminences, occasionally, rough under a 

 lens : the spini-form coraliites numerous but not inflecting the walls 

 of the coraliites; apertures or calices rounded, n in 3 mm.; intersti- 

 tial cells abundant, unequal, 11 rounded at the surface:" tangential 

 sections just below the surface show the coraliites to be rounded, with 

 moderately thick walls : interstitial cells sharply defined, sub-angular, 

 unequal, three or four to each corallite : spiniform tubuli strong, two 

 to each corallite : mainly in the walls, which are occasionally bent 

 inward ; at a deeper level, the walls are thinner : tabulae abundant in 

 all of the tubes, mainly horizontal in the axial, but vesicular in the 

 peripheral region. (Pal. of Minn., vol. 3 of Geol. and Nat. Hist. 

 Survey, I893, p. 234 as Homotrypella rustica. 



Locality. — Various places in Ohio, Indiana and Minnesota. 



85. — M. (Fistulipora) granulifera (Ulrich) 1879. 



Corallum ramose with sub-cylindrical branches, dividing dicho- 

 tomously at varying distances, sometimes irregularly thickened or 

 nodulated and having a diameter of from two to five lines : surface 

 smooth or with obscure tubercles or maculae : in the former case com- 

 posed of tubes slightly larger than the average and in the latter 

 of minute tubuli : calices unequal, varying from circular or oval to 

 sub-polygonal : intercellular spaces thick and with numerous small 

 coraliites, in unworn specimens appearing like spines, but in worn 

 examples showing a tubular character : tabulae few in the axial region 

 but becoming more numerous toward the surface : walls thin. (Jour. 

 Cin. Soc. Nat. Hist., vol. 2, 1879, P- I2 ^ as Chcetetes : Homotrypella 

 granulifera Ulr. , 14th Rept. Geol. and Nat. Hist. Sur. of Minn., 

 1886, p. 83.) 



