302 The Crinoidea of the Lower Niagara Limestone. 



nation, enough can be made out to show that the larger proportion 

 are specifically distinct from those found in the underlying shales. 



Among the species determined are Caryocrinus ornatus, Say; 

 E ucalyptocrinus i^iconsjjectus, Ringueberg ; Heterocystites arma- 

 tus, Hall ; Lecanocrinus macropetalus, Hall ; Periechocrinus spe- 

 ciosus, Hall ; Dimerocrinus immaturus, Hall ; Galceocrinvs con- 

 tractus, Ringueberg ; and the five new species described below. 



CallicrinilS acaiithinus n. sp. Pi. Ill, fig. 1. — Calyx sub-angulate, 

 low, ornamented with spines, nodes, and radiating ridges. Ten of the spines 

 are long and slender and spring in a circle from the middle of the calyx, being 

 directed outwards and upwards, their apices reaching to a point about as high 

 as the top of the calyx. Base nearly as broad as the rest of the calyx ; deeply 

 excavated by a wide pentagonal depression, which slopes upwards and in- 

 wards from the narrow rim of the excavation to about one-third of the height 

 of the sides, its angles are directed radially and present at aboitt the middle 

 of the first radials. Basal plates small, and of the usual form. First radials 

 bent abruptly outwards and upwards near the middle ; their outer upper sides 

 being curved inwards so as to conform to the pentagonal base and meet the 

 margins of the adjoining first radials without the formation of an angle at the 

 sutures ; they have six ridges, usually strong, radiating from their center, a 

 median one directed inwards towards the columnar facet, lying in the angle of 

 the basal excavation ; two laterally and slightly inwards meeting the corre- 

 sponding ones from the opposite plates and forming the rim of the base, they 

 also represent the point of the upward curvature of the plates ; the next two 

 are directed outwards and upwards towards the sides upon which rest tlie 

 large inter-radial plates, these are the least prominent of any at the point of 

 radiation, but become rapidly more prominent and strong at the margin of the 

 plate ; the remaining ridge is projected outwards on a plane with the base, 

 as far as, and on a line with, the sides of the calyx where it is abruptly trun- 

 cated by a rectangular turn upwards, thus forming a subacute node or spine. 

 The second radial is broader than high and has a strong median ridge extend- 

 ing from one lateral margin to the other. Third radial gradually elevated 

 from the lower and outer sides forming the sloping base of one of the long 

 spines which it bears, and at times has slight ridges meeting those from the 

 adjoining large inter-radials which are similarly elevated and spiniferous. 

 The apices of the plates, and consequently the bases of the spines being on 

 the same plane, in the third radials and the large inter-radials. The spines 

 of the third radials are flattened antero-posteriorly and those of the inter- 

 radials laterally. The rest of the plates forming the calyx all have their 

 ventral portion elevated into nodes or ridges and are of moderate size. Inter- 

 maxillary plates, arms, column, etc., unknown. 



This remarkable crinoid has been known to me for quite a num- 

 ber of years past from disconnected plates, but it was not till some- 

 what over a year ago that a specimen was found which preserved a 



