34 BULLETIN 64, UNITED STATES NATIONAL MUSEUM. 



certainty. The nearly complete calyx labeled in Troost' s hand- 

 writing Cupellsecrinites striatus is of the same species as Marsipocrinus 

 striatus Wachsmuth and Springer. In connection with their descrip- 

 tion these authors do not refer to the previous use of the name 

 striatus by Troost, and were, perhaps, unaware of the identity of his 

 species with theirs. The Cupellsecrinites striatus Troost differs from 

 that of Wachsmuth and Springer in having the angle of the basi-radial 

 sutures only faintly indicated or absent, but this is a variable feature, 

 as shown by a specimen in which one of the sutures is sharply angled 

 and another straight. 



Cupellsecrinites infiatus Troost is said to differ from C. striatus in 

 having a more elevated calyx, but this appearance of greater height 

 is produced by the preservation on the former of a portion of the 

 tegmen. The height of both is about the same to the top of the first 

 interbrachials, and they are included in one species. 



Marsipocrinus striatus differs from M. tennesseensis Roemer in the 

 finer surface striae, the strongly beveled sutures and the depressed 

 base. 



Formation and locality. — Brownsport limestone, Eucalyptocrinus 

 zone of the Beech River formation. Decatur County, Tennessee. 



Cat. Nos. 39926, 39934, TJ.S.N.M. 



MARSIPOCRINUS MAGNIFICUS (Troost). 

 Plate 10, figs. 5, 6, 7. 



Cuppellsecrinites magnijicus Troost, Proc. Amer. Ass. Adv. Sci., II (read 1849), 



1850, p. 61 (nomen nudum). 

 Cupellxcrinus magnijicus Shumard, Trans. Acad. Sci. St. Louis, II, No. 2, 1866, 



p. 361 (catalogue name). — Wachsmuth and Springer, Rev. Palseocrinoidea, 



II, 1881, p. 230 (catalogue name). 



The original description is as follows: 



The perfect preservation of the specimen from which this description is drawn up 

 (it being siliceous, and without blemish), the beautiful insculpted surface, and the 

 regular dome-shaped mammillary capital cover [tegmen] surrounded with five rostra 

 or beak-like projections which adorn the angles, giving it a pentagonal form, caused 

 me to adopt for this species, the name of magnijicus. 



Pelvis [base] — pentagonal with curvilinear margins — a pentalobed alimentary aper- 

 ture [lumen], in the center, surrounded with a corrugate elevated circle — the im- 

 pression of the column shows that it was cylindrical — the elevated circle is enclosed 

 in a broad corrugate border reaching to the edge of the pelvis. From each of the angles 

 of the pentagonal pelvis proceeds a row of tubercles which meet together on the costals 

 [radials] at a line of similar tubercules running from two opposite angles of the hexa- 

 gon, parallel with the sides by which the inferior half of the costals [radials] is divided 

 into three equilateral triangles, so that the pelvis [base] is surrounded by 15 equilateral 

 triangles — the interior space of these triangles is irregularly tuberculated, such is also 

 the case with the superior half of the hexagonal costals [radials] which form part of 

 the elevated sides of the cup, while most of the lower half forms with the pelvis [base] 

 the bottom of it. 



The scapulars [secundibrachs], which rest upon the superior margin of the hexa- 

 gonal costals [radials] exhibit at the lower part a kind of rosette [the small primibrach], 



