VON BUCH ON THE CYSTTDEA. 39 



plete the cup. The mouth is in the centre of the summit, slightly- 

 prominent or probosciform, and covered with very small plates. The 

 ovarial orifice is covered with five small valves, rarely preserved, 

 arranged like a star; and in each of the valves is a small orifice 

 open to the interior of the plate, as in SphcBronites, but situated 

 exactly in the middle of the valve, and probably serving for the 

 protrusion of the eggs. There is a remarkable arrangement admi- 

 rably shown in a specimen in the Royal Collection of Minerals at 

 Berlin, which clearly proves that this opening cannot be looked 

 upon as an anal aperture. The aperture is placed at the junction 

 of two lateral and one summit plate, and the lateral plate on the left 

 side, which reposes on the intersection of the two basal pentagons, 

 is divided throughout into two smaller plates which are attached at 

 the broader sides of each ; appearances which must manifestly stand 

 in close relation to the arrangement of the internal organs. The 

 anal opening is placed a little to the right, between the ovarial ori- 

 fice and the mouth, but it is often hardly visible. 



Five blunted corners may very distinctly be traced on this species, 

 reaching from the pelvis quite up to the summit. They are unques- 

 tionably indications of arms which have vainly endeavoured to 

 become liberated towards the summit and extend themselves up- 

 wards. 



Although the specimens described exhibit no traces of rhombic 

 striae, this may in all probability have arisen from the worn condition 

 of their surface. 



Locality : — Pulcowa, and also Narwa on the Narowa, according 

 to M. Blasius. 



Mr. Austen states that Sycocrinites exhibits three dorso-central 

 (pelvic) plates, which form a pentagon, and supporting five periso- 

 mic (lateral) plates, while five other plates rise in a dome-like form 

 to the central mouth. He adds that an anal (ovarial) orifice is found 

 at the side, and that there are no arms. This is manifestly the de- 

 scription of a Cryptocrinite (so named in 184-0); but this author 

 does not state the locality of his specimen, and not even whether it 

 is English ; and this is so much the more to be lamented, since it is 

 important to know, in case of this locality being, as it probably is, 

 in England, with what Crinoidea it was found associated. The Sy- 

 cocrinites clausus has however an additional row of lateral plates, 

 and would properly form a distinct genus. 



The so-called Asterocrinus of Austen, provided with ambulacra, 

 evidently belongs to the Blastoidea of Say, and approximates closely 

 to the Pentremites. 



Some fossils described by M. Eichwald and named Cyclocrinites 

 Spaskii (Urw. Russl. p. 48. tab. 1 . fig. 8) and Heliocrinites eckiuoidcs 

 (Duke of Leutchenberg, p. IS.tab. 2. fig. 11, 12) are too indistinctly 

 known to be identified. They are round bodies not having any vi- 

 sible place of attachment for a stem, and neither mouth nor ovarial 



