PLATE VIII, 



The Letterins is the same in all the Figures. 



A. Axial cord of ray or ann. 



a'. Its branches. 



ai. Primary interradial cords. 



£, Basal ring. 



By First brachials. 



C. Cocloni or body-cavity. 



c. Network of connective tissue within the coclom. 



ceo. Interradial portion of the circular commissure. 



ch. Cavities of the chambered organ. 



fg. Fore-gut. 



O. Gut. 



L. Interradial ligament. 

 I. Basiradial ligament. 



Id. Dorsal ligament. 



li. Interarticular ligament. 

 El. First radials. 

 R,. Second radials. 

 iij. Tliird radials. 



re. Rectum. 

 ■n)i. Muscles uniting the first and second radials. 



V. Vascular axis of stem. 



X. Plexiform gland. 



Bathycrinus aldrichianus, Wyv. Thorns. 



Fig. 3. Horizontal section of the calyx at the level of the basiradial 



suture, 



Diam. 



Fig. 1. Vertical section of the calyx, with the lower part of the disk, . x 20 

 Fig. 2. Horizontal section of the basal ring, . . . . x 45 



X 45 



Page 

 235 



22G 



228 



Fig. 4. Horizontal section of the radial pentagon at the level of the 



circular commissure, . . . . . x 20 230 



Fig. 5. Horizontal section of the calyx, through the articulation of the 



first and second radials, . . . . . x 20 230 



Fig. 6.' Horizontal section of the calyx, through the upper part of tlie 



second radials, . . . . ' . x 20 



231 



Fig. 7." Horizontal section of the calyx, through tlie middle of the 



third radials, . . . . . . x 22 



231 



Fig. 8. Horizontal section of the disk, through the articulation of the 



first and second brachials, . . . . x 20 



232 



• In the upper part of this fitjnre a should be «', as in the lower part. 

 - On the U-ft of this fisrure / should be L. 



