EXPLANATION OF TLATE I. 



PACK. 



Modiolopsis corrugata, n. sp., 79 



Fij( I, left side view, natural size. 



Modiolopsis longa, n. sp., 80 



Fig. 2, left side view ; Fig. 3, cardinal view, natural size. 



Modiolopsis sulcata, n. sp 80 



I'ig. 4, left side view, natural size. 



Protoscolex magiuis, 11. sp., 83 



Fig. 5, natural size ; FMg. 6, magnified two diameters. 



Cyclocystoides cincinnatiensis, 11. sp., 84 



Fig. 7, natural size ; F'ig. 8, magnified two diameters. 



Aviculopecten germanus, n. sp. Si 



F'ig. 9, left valve, natural size. 



Agelacriniis pileus ? 85 



Fig. 10, under side, showing part of the structure. 



Orthodesina niuiuluin, 11. sp., 82 



Fig. II, left valve, sliglitl}- broken at the posterior end ; I'ig. 

 12, cardinal view, natural size. 



Cyclocystoides, sp., 85 



F'ig. 13, fragment of superior side, showing part of the ring, 

 the outer rim having mammillary scars, and beyond and 

 below this, plates from the other side ; on the interior of 

 the ring may be seen the commencement of the internal 

 rays, and below this the plate belonging to the other side ; 

 Fig. 14, plates on the dorsal si<le of the same specimen ; 

 Fig. 15, the same magnified two diameters. 



Holocystites affinis, 11. sp., 87 



I'ig. 16, anterior side view ; F'ig. 17, posterior side view ; Fig. 

 iS, summit view. 



