{oie 
Pais ar Pes ee 
r ‘ 
} 
REPORT ON THE CRINOIDEA. 11 
immediately beneath the articular ridge (Pl. X. figs. 1-4; Pl. XX. fig. 7; Pl. XXXa. 
fig. lla; Pl XXXII. figs. 6, 8-11, 15), and corresponding to the single pit which 
lodges the third lgamentous bundle in the trifascial articulations of Bathycrinus 
(Pl. Vila. figs. 16, 20, 22, dd’). In Millericrinus, and more especially in Apiocrinus, the 
portion of the dorsal fossa outside this central pit is enormously expanded ; and the true 
articular surface becomes relatively insignificant. 
The pairs of fossee are symmetrical on the two sides of each articular face in the 
first and second radials (PI. Vila. fig. 15; Pl. XII. figs. 20, 23; Pl. XXI. figs. 5c, 6d); 
but in the ordinary arm-joints, which have more or less oblique terminal faces and bear 
pinnules at their sides (Pl. VIla. fig. 21; Pl. XXI. figs. 4b, 4c), there is a disturbance 
of the symmetrical arrangement of ridges and fossee which is so very evident in the 
calyx of all Neocrioids (Pl. VIIb. fig. 5; Pl. VIIa. fiz. 7; Pl. X. fies: (i, 435 Pl. ei 
fig. 15; Pl. XVIII. fig. 4; Pl XXX. fig. 3; Pl. XXXIV. fig. 7), with the exception of 
Holopus and its allies (PI. III. figs. 1, 2; Pl. V. fig. 1). 
