510 HERRICK E. WILSON 



PLATE III 



Steganocrinus pentagomts Hall 

 No. i. — Posterior view of abnormal form of PI. II, No. 15. 

 No. 2. — Tegmen of same specimen, showing position of anal tube. 

 No. 3. — Posterior view of normal specimen in Springer collection. To be 

 compared with No. 1. 



Hexacrinus dongatus Goldfuss. Springer collection 

 No. 4. — Basal view of normal form. Basal formula ab — cd—cx — . 

 Note reduction of posterior radials. 



Hexacrinus anglypticus Goldfuss. Springer collection 

 No. 5. — Basal view of abnormal form, showing loss of posterior basal 

 suture and reappearance of left-posterior suture. Anchylosis of anterior 

 basals normal. Basal formula, b—cd—ea—\ factor x may or may not be 

 present. 



No. 6. — Basal view of another abnormal specimen, showing loss of right- 

 anterior basal suture and reappearance of anterior suture. Basal formula, 

 ab—c—dcx— . 



Talarocrinus patci M. & G, Springer collection 



N0.7. — Basal view of normal specimen. X 2. Basal formula, dbc—dex—. 



No. 8. — Basal view of abnormal specimen, showing reappearance of left- 

 posterior basal suture. X2. Basal formula, a — be — dex—. 



No. 9. — Basal view of another abnormal specimen, showing reappearance 

 of left-anterior basal suture. X2. Basal formula, ab — c — dcx—. 



No. 10. — Basal view of another abnormal specimen, showing loss of 

 posterior basal suture and reappearance of left-posterior and right-anterior 

 sutures. X2. Basal formula, bc — d — ca — . Factor .v may or may not be 

 present. 



Pterotocrinus cirnarius Lyon, Springer collection; Tegmen figured by 



Wachsmuth and Springer, ref. 39, PI. LXXIX, Figs. 7a, 7^ 

 No. n. — Basal view, showing great reduction of anal plate, and asym- 

 metry of posterior radials. Basal formula, dbc—dex—. 



Dichocrinus inornatus W. and Sp. Springer collection 

 No. 12. — Lateral view of normal specimen. X i\. 



No. 15. — Tegmen of normal specimen showing flexible condition of anal 

 tube and interambulacral areas. X2. 



Plcitycrinus symmctricus W. and Sp. Springer collection 

 No. 13. — Lateral view, showing similarity to No. 12. Xij 

 Xo. 14. — Tegmen of young specimen, figured by ref. 39, PI. LXIX, Fig. 



ir. Note flexible condition of anal tube and interambulacral areas, and 



general similarity to Xo. 15. X- 1 . 



