3K0 PROCREPINGS^OP THE ACADEMY OF [1885. 



EXPLANATION OF THE PLATES. 



I'h, following letU ra art employed throughout all the plates. 



a azygous plates. 

 b basals. 



br = brachials. 



e = column, and sections of the column. 

 <■'/ centrodorsal. 

 cr = compound radial. 



d = interaxillaries. 



e = covering plates (Saumpliittchen). 



h = nou-arm-bearing radials. 



i — interradials (dorsally and ventrally). 



o = oral plate or plates. 



p proxiinals. 



r = radials in the calyx and summit. 



r 1 = first radial. 



r 2 = second radial. 



t = plate of the ventral tube. 



u = underbasals. 

 wp = water-pore. 



I anal plates. 

 .10 = anal opening. 



rr - posterior radials enclosed in the ring of proximals. 



J= interradially. 

 ZZ azygous interradius. 



The diagrams on Plate 6 are designed to show the position of basals 

 and underbasals to the different parts of the column ; those of Plates 7 

 and 8. to show the relation of the summit-plates with each other and with 

 adjoining plates. 



EXPLANATION OF PLATE IV. 



Fig. 1. Cupressocrinus abbreviatus Goldfuss, showing the consolidated 

 muscle-plates, the axial canals, arm openings, and the position of the 

 anal aperture. 



Fig. 2. Ventral aspect of Cyathocrinus Gilesi. The interradials crowned 

 by mliercles, and resting against the incurved ends of the radials. 



FlO. 3. similar view of another specimen, showing the interradials in the 

 same position, but partly covered by perisomic plates, which connect 

 with the outer edges of the incurved ends of the radials. 



Fig. 4. Impression "t the ventral side of a specimen of Teleiocrinus. The 

 radiating ridges represent paired canals along the inner floor of the 

 test. The original is in the collection of Mr. R. R. Rowley. 



Fig. 5. Ventral side of D»rycrinue Missouriensis. The ambulacral tubes 

 are exposed only close to the arm-bases, disappearing toward the centre 

 beneath the infiltrating material. 



