70 BULLETIN 64, UNITED STATES NATIONAL MUSEUM. 



support two arms while the two between which the elongated intercostal [anal] termi- 

 nates, support three arms. Of the seven interscapulars [interbrachials], five [four] 

 are elongated sub-hexagonal and support upon the two oblique superior edges two 

 small plates; two are broad and short — and the seventh, which is elongated and con- 

 tracted projects beyond the other interscapulars [anals], between the three handed 

 arms. The latter is placed immediately upon the elongated, intercostal, [first anal] 

 and the five [four] elongated, together with the two broad interscapulars [interbrach- 

 ials], are placed in the re-entering angles formed by the junction of the costals [radials]. 



Upon three of the pentagonal scapulars [primaxils] are placed two arms while those 

 which are next to the elongated and the two broad interscapulars [interbrachials] 

 have three arms. 



The whole of this construction forms an irregular pentagonal or star-shaped plane, 

 supported by a cylindrical column attached to its centre, and is covered by a pyra- 

 midal or conical coronal integument, composed of tumous polygonal plates, which 

 terminates in a long proboscis. 



I can say nothing respecting the hands and their subdivision. All my specimens 

 in this respect are defective. 



Judging from a specimen in my collection where a fine body is placed on a fragment 

 of the rock in which it occurs and is surrounded by columnar joints, its column was 

 composed of joints with radiating articulating surfaces having a circular or pentagonal 

 alimentary canal [lumen]. 



I discovered it near White's Creek Springs, Davidson County, Tennessee. 



troost's diagram showing arrangement of plates of a. tuberculosus. 



Observations. — The specimen representing this species is missing, 

 and in the absence of further information Doctor Troost's description 

 and figures are reproduced as they stand. The species is referred to 

 Alloprosallocrinus , as it appears to be related to that genus in the 

 form of the body and arrangement of the plates, so far as it can 

 be determined. 



There is a discrepancy between the description and the figures in 

 representing the position of the first anal plate. The figures show 

 an hexagonal first anal followed by three elongate plates, while the 

 description places the central elongate plate between the radials. 



