Plate 1. 

 COMANTHOCRINUS INDIANENSIS (Miller and Gurley) 



Fig. 1. Basal view of a typical specimen, showing varying forms of the reduced 

 and modified first primibrach, extra plate in second range of pos- 

 terior interradius, and the origin of the fixed pinnules as well as 

 position of the sockets where they become free. X3/2. 

 Clark County, Indiana. 



2. Profile vieAV from left side of same specimen; showing the great pre- 



ponderance of the tegmen in height, the bulging on the anal side, 

 and course of pinnule-ambulancra of the fixed pinnules. X3/2. 



3. Posterior view of same; showing the strong median row of large plates 



leading from the narrow anal plate of the dorsal cup to the base of the 

 sub-central tube. Openings for fixed pinnules are seen here also. 

 X3/2. 



4. Interradius of another specimen from the same locality, showing course 



of pinnule-ambulacra, now represented by open slits. X3/2. 

 .5. Posterior view of larger specimen from same locality, showing the 

 strong anal series in the tegmen, base of anal tube, and the asym- 

 metrical bidging of the tegmen not coinciding with the median row, 

 but following the course of the gut. The specimen is much silicified, 

 and the apperance of numerous small plates in the swollen part may 

 be in part misleading. X3/2. 



6. Dorsal view of specimen with arms, from Canandaigua Lake, New York. 



It shows the heavy, uniserial arms, with two pinmde-sockets to the 

 margin of each bracliial beyond the fifth, and some of the very 

 slender pinnules. 



Hamilton: Louisville area, and New York. 



COMANTHOCRINUS PRISCUS, new species 



7. Basal view of a free dorsal cup; showing the broadly concave base, 



large stem-lumen, deeply rounded rays, and V-shaped brachials, 

 with the fixed pinnules leading from the secundibrachs; also the 

 reduced first primibrach, and left posterior position of small basal. 

 The posterior interradius in this specimen is slightly contracted by 

 pressure. 



8. Interior (ventral) surface of same specimen (the tegmen wanting), 



drawn with anal side up for better comparison of structures. It 

 shows the position and relation of the fixed pinnules, and the exact 

 plates upon which they originate (not all visible from the dorsal side); 

 and the intricate complex of grooves and ridges passing from plate to 

 plate, marking the lodgment of nerve cords. 



9. Interior view of another specimen showing the same structures as the 



last with slight difference in detail. In this the small basal except- 

 tionally is in the left anterior position. (See also text figs. 1 and 2.) 

 10. Sketch showing position of pinnule openings and course of ambulacra 

 leading to them as seen in Marsipocrimis, represented by elongate 

 slits in ComcmtJincrinKS and Dolatoerinus; for comparison with figin'e 

 4. From author's paper on Scyphocrinus, p. 42. 

 Onondaga: Louisville, Kentucky. 

 60 



