INSERTAE SEDIS 45 I 



Edriocrinus becraftensis, J. M. Clarke 



Edriocrinus becraftensis Clarke, Mem. Ill, New York State Museum, igoo, p. 62, pi. 9, figs. 12, 13. 



A rather large species, known by the base only. Base very elongate, nar- 

 rowly conical, slightly widening upward. Height to width about 1 to .75 ; 

 type specimen 30 mm. high, 15 mm. wide at upper end, and 8 mm. near the 

 lower rounded extremity. 



Type. New York State Museum, Albany. 



Horizon and locality. Oriskany sandstone, Becraft Mountain, Columbia County, New 

 York. 



Section II 

 Attached through life by encrusting base adapted to the form of objects to which attached. 



Edriocrinus adhaerens n. sp. 

 Plate LXXVI, figs. 16-18 



A very small species; only the fused base known. Base low, spreading 



more or less at the encrusting surface, enclosing a broad shallow cavity; wall 



thin. Height to width of base about as 1 to 2. Specimens ranging from 5 to 



10 mm. in diameter. Maximum specimens are nearly as wide as minimum 



specimens of E. dispansus having the rounded base fully developed, thus 



making it improbable that this is the young stage of that species. 



Types. In the author's collection. 



Horizon and locality. Helderbergian, Linden formation, Hardin and Benton counties, 

 Tennessee. Usually found attached to shells or Camarocrinus bulbs. 



Edriocrinus pyriformis Hall 

 Plate LXXVI, figs. 19-21 



Edriocrinus pyriformis Hall, 15th Rep. New York State Cab. Nat. Hist. 1862, p. 115 (sep. p. 87), text- 

 figs. 1 and 2. — Kirk, Proc. U. S. Nat. Mus. 41, 191 1, p. 112, pi. 11, fig. 9. 



A medium-sized species, known only by the calyx. Base elongate, cylin- 

 drical, with concave scar for attachment. RR long, expanding upward, giv- 

 ing a turbinate aspect to the radial circlet; contracting .toward the upper 

 margin which is more or less abruptly bent in, so that the diameter at the 

 radial facets is considerably less than that of the expanded portion below. 

 Anal plate narrow, projecting above radials. 



Hall's figures 1 and 2, on page ill (87) of the 15th Report were drawn from three 

 specimens, — figure 1 being a composite based upon a flattened calyx and two perfectly 

 rotund sets of radials, and figure 2 a distal view of one of the latter. They show the form 

 and proportions of the species with entire accuracy. Measurements of six specimens give 

 the following average dimensions : Height of calyx, 33 mm., of radials, 18 mm., of base, 

 15 mm.; width at zone of greatest expansion, 18 mm., contracting to 13 mm. at radial 

 facets ; at basi-radial suture 10 mm. ; base at surface of attachment, 10 mm. The extremes 

 depart but little from this mean. This species is not quite constant in the sessile base, as 

 among six specimens with base preserved, five have a broad concave scar, one has the 

 scar almost completely overgrown ; while a seventh, detached base only, associated with the 

 others, is rounded. 



