19 



structed in like manner and bears three arms. The other lateral 

 ray bears upon each of the upper sides of the third primary 

 radial two secondary radials, the last being axillary and sup- 

 porting on each upper sloping side two tertiary radials, which 

 gives to this ray four arms. In the ray opposite the azygous 

 area there are three secondary radials, which gives to this ray 

 two arms. There are, therefore, fifteen arms in this species, 

 as shown by the ambulacral openings to the vault. 



There are three regular interradials in each area, one large, 

 the other two small and somewhat elongated. The azygous 

 area is very peculiar, as the proboscis having the azygous 

 orifice separates the tertiary radials and projects below the 

 ambulacral openings and occupies nearly half the azygous 

 area. The first plate is heptagonal, in line with the first 

 primary radials and the largest plate in the body. There are 

 three plates in the second range, the middle one being the 

 smaller and supporting the plates that surround the azygous 

 orifice. In the third range, on one side of the recumbent pro- 

 boscis or azygous ridge, there is one rather large plate, and all 

 the' other plates in the area are small and form part of the 

 round recumbent proboscis. The vault is highly convex, and 

 has a capacity equal to or greater than that of the calyx. It 

 is covered with small, convex, polygonal plates. Upon the 

 azygous side of the center a convex elevation arises that be- 

 comes more defined as it passes down between the ambulacral 

 orifices and finally projects, like the end of a proboscis, below 

 the arms in the upper third of the azygous area. It ap- 

 pears like the recumbent proboscis in Siphonocrinus armosus, 

 though not projecting quite as much. Probably the word 

 "proboscis" should not be used in the definition, for it is 

 merely a rounded ridge from one side of the vault that termi- 

 nates in a hemispherical projection that bears an orifice in the 

 upper part of the azygous area, as shown in the illustration. 



This species is distinguished by its general form, convex vault, 

 recumbent proboscis with orifice below the arms, and by its 

 fifteen arms, from all other species. By some it might be re- 

 ferred to DorycriniiS) but we think it is clearly a Batocrinus. 

 Pound in the Keokuk Group, at Boonville, Missouri, and now 

 in the collection of S. A. Miller. 



