56 The Ohio Journal of Science [Vol. XXI, No. 2, 



theca is due to compression. The height of the globular part of the 

 theca is about 20 mm. At the base it appears to have narrowed strongly 

 to a short stipe, probably not over 15 mm. in length, although this part 

 of the theca is not preserved. 



The oral aperture is at the base of a deep, laterally elongated, tri- 

 angular pit, the anterior food-groove departing from the anterior angle 

 of this pit, the right anterior and right posterior food-grooves departing 

 from the angle on its right, while the left anterior and left posterior food- 

 grooves separate from each other at a point about a millimeter from 

 the left angle of the pit. The most characteristic feature of the species 

 consists in the relatively great width and depth of the food-grooves and 

 their almost V-shaped cross-section. Along the proximal half of the 

 length of the food-grooves their width equals about 1.5 mm. Along the 

 sides of the food-grooves there are depressions or grooves which may 

 locate the sutures between the bordering plates. If they represent 

 branches of the food-grooves, then it should be observed that they lead 

 to no facets for brachioles. Parts of the surface are so well preserved 

 that the absence of any evidence of the presence of brachioles should be 

 emphasized. 



The food-grooves complete more than half of a circuit, the distal end 

 reaching the lower side of the globular part of the theca. The distal end 

 of theleft ant erior food groove curves upward toward the anterior food- 

 groove and becomes parallel to the latter again for a short distance, as 

 indicated in Fig. 5B on Plate I, and also in the figure accompanying 

 Miller's description. The anal opening is circular and 3 mm. in diameter. 

 No trace of the anal pyramid or of the small plates covering the food 

 grooves remains. 



The surface is strongly and irregularly granulose, most of the 

 granules being about one millimeter, or a little less, distant from each 

 other. Where the surface is worn, there are diplopores, the individuals 

 of each pair being less than half a millimeter from each other. Where 

 the surface is not worn, there is no trace of these diplopores. 



Locality and Horizon. — From the Osgood formation in 

 Jefferson County, Indiana. Specimen numbered 6019 in the 

 Walker Museum of Chicago University. 



11. Gomphocystites sp. 



(Plate III, 2 A, B.) 



Theca depressed globular, narrowed strongly at the base to a short 

 stipe probably a little over 5 mm. in length. Along part of the globular 

 portion of the theca the sides appear flattened, but this may not be a 

 constant feature. There is no tendency toward straightening of any part 

 of any of the food-grooves as in the case of Gomphocystites indianensis. 

 The distal ends of these food-grooves reach the lower part of the plat- 

 tened sides of the theca. The distal end of the left anterior food-groove 

 probably curves upward toward the anterior food-groove, as in Gompho- 

 cystites indianensis. Along part of the anterior food-groove, several 



