Plate 8. 



DOLATOCRINUS SPINOSUS Miller and Gurley 



Fig. 1. A'si^ecimen below average size; basal view, showing strong radial ridge 

 limited to radial and IBr, and rather pitted ornament. 



2. Lateral view of same, showing stout spines on the tegmen, and pinnule 



openings between arm bases. 



3. A very young variant, with disproportionally high tegmen, and ridges 



extending to arms. Probably should be referred to D. insuetus — 

 fig. 8 below. 



4. A small specimen with extremely fine striate ornament, and very high 



knifelike ridges on radial and IBr. 



5. An average specimen with typical striate ornament, and usual shape 



of large iBr; remains of high radial ridges limited to IBr. 



6. Another specimen with variation in shape of the large iBr, which is 



nearly acuminate instead of broadly truncate. 



7. Tegmen of the same, showing the broken-off bases of strong spines, the 



arrangement of plates, and position of pinnule openings. 



DOLATOCRINUS INSUETUS Rowley 



8. Basal view of specimen with perfect typical ornament, and showing 



the radial ridges extending to the arms; the knifelike projections of 

 the ridge are broken off. 



All Onondaga: Louis\-ille area. 

 18:^.081—21 6 67 



