552 



GEOLOGY OF NORTHWESTERN TEXAS. 



APPENDIX. 



HADROPHYLLUM, E. & H. 



Fig. 60. 



Fig. 60a. 



Fig. 60b. 



Fig. 61. 



Fig. 61a. 



Fig. 61b. 



EXPLANATION OF PLATE. 



Fig. 60. Calycular view, natural size. 



Fig. 60a. Under side of same example. 



Fig. 60&. Side view of same example. 



Fig. 61. Calcyular view, natural size of a smaller example. 



Fig. 61a. Under side of same example. 



Fig. 61&. Side view of same example. 



H. aplatus, sp. nov., Cummins. 



Corallum flattened, discoidal; periphery attenuated; under side nearly flat 

 and marked by concentric wrinkles; upper side convex; fossette deep, reach- 

 ing from the centre to the periphery; septa prominent, extending from the 

 fossette to the margin, single, numbering from twenty-one to twenty-five. 

 Transverse diameter twenty-six mm. Thickness seven mm. in full grown 

 individuals. 



The bilobed bodies which appear near the edge of the specimens, and which 

 are shown in the drawings, are perhaps parasites. 



This species differs from H. glans, White, in the number of the rays and 

 the length of the corrallum. 



Locality. Bend Division of the Carboniferous, which is at the base of the 

 Coal Measures series in Texas. 



