78. CONTRIBUTION TO 



NUCLP:0CRINUS VE RNEUILI, Var. Inflatus, N. Var. (Rowley) 



Plate 20. Figs. 3, 4-5. 



This variety is characterized by its full interambulacral areas, almost or 

 quite smooth plates and rather broad base, due to the ventricose character of 

 the body. 



The anal plate is rather prominent, rising above the general contour and 

 more or less produced at the summit. The ventral side of this form is covered 

 over by a roof of plates, as in the illustration and the basal concavity is rather 

 large, due to the shape of the body. 



The ambulacra are rather narrow and the surface markings, though indis. 

 tinct, differ little from typical vemeu'dl. 



From the middle division of the Devonian at the Falls of the Ohio, and the- 

 figured specimens belong to the collection of Mr. G, K. Greene. 



NUCLEOCRINUS VERNEUILI, Var. Sulcatus. N. Var. (Rowley.) 



Plate 26. Figs. 6, 7-8. 



This variety is chiefly characterized by the very distinct grooves or sulca- 

 tions occupying about one-fourth of the width of the interambulacral areas and 

 extending from base to summit, being quite deep between the ambulacral tips. 

 These sulci divide the body into distinct, flattened lobes and give to the areas 

 between them a canoe shape, the centers of which is occupied by the ambulacra. 



The ornamentation of the interambulacral areas, bordering the ambu- 

 lacra, are both cross lines and linear elevations, passing to the sulci a little 

 obliquely. 



The ornamentation of the depressed areas or sulci is cross, wavy or M- 

 shaped lines. 



The special anal plate is furrowed down the middle, aud but little elevated 

 above the general surface. 



Its ornamentation is very similar to that of the other sulci. 



The ambulacra are broader than in variety lutfatus and give room below 

 for a less basal cavity. 



The summit is covered by small plates as in Verneuili, and there are tea 

 spiracles as usual in the genus. 



The radials bear the same proportion in length to the interradials as they 

 do in VerneulU. 



Horizon, locality and collection same as last. 



