PLATE Villa. 



The Lettering is the same in all the Figures. 



A. Axial cord of arm. 



a'. Its branches. 



ac. Ambulacral epithelium. 



£„. I'econd brachial. 

 b. Radial blood-vessel. 



Jr. Plug of calcareous tissue, called a basal rosette by Sars. 



cc. Coeliac canal. 

 ceo. Interradial portion of circular commissure. 



cp. Covering plate. 



O. Gut. 



gc. Genital cord. 

 gc'. Genital canal. 

 ico. Intraradial portion of circular commissure. 



/. Arm-joint. 



Id. Dorsal ligament. 



li. Interarticular ligament. 



mj). Muscle -plate. 



01. Ventral or ambulacral nerve, 



i^i. First radial. 



re. Rectum. 



rm. Muscles uniting the first and second radials. 



ste. Subtentacular canal. 



T. Tentacle. 



rrf. Ventral radial furrow. 



ly. Radial water-vessel. 



X. Plexiform gland. 



Figs. 1-3. Bathycrinus gracilis, Wyv. Thorns. 



Fig. 1. Head and upper part of stem, . 



Fig. 2. Middle part of stem, .... 



Fig. 3. Lowest part of stem, . . . . * 



Fig. 4. Ventral portion of a transverse section of an arm. 



Fig. 5. An entire section through the middle of an arm-joint, 



Figs. 6-8. Rhizocrinus lofotensis, Sars. 



Fig. 6. Horizontal section through the lower part of the radials, of 



which there are six, . . . . . x 35 250 



Fig. 7. Horizontal section of the calyx of the same individual at the 



level of the articular faces of the radials, . . . x 35 252 



Fig. 8. Horizontal section of the disk of a pentamerous specimen at 



the level of the second brachials, . . . . x 40 254 



