1881,] NATURAL SCIENCES OF PHILADELPHIA. 359 



differs, according to description, by having a quadrangular column, 

 four basals and no underbasals, thus bringing it in close proximity 

 to Mariacrinxis and Melocrinus, and among the Actinocrinidte. 

 There is something in the habitus of the genus that leads us to 

 think it should be associated with the Rhodocrinidee, and that it 

 had underbasals which were not disclosed. 



!No Actinocrinoid has ever been discovered in which the inter- 

 radial field, except at the " azj-gous " side, extends to the basal 

 disk', such, however, seems to be clearly the case in Xenocrinus 

 penicillus. We leave the discussion of this genus to our future 

 appendix, as we hope to have an opportunity to examine some of 

 the specimens. 



Another of Miller's new species is described with four basals 

 and a quadrangular stem ; but, contrary to the former, here only 

 the interradial area at the posterior or anal side descends to the 

 basals. Miller refers the species to Glyptocrinus with which it 

 has no doubt close affinities, but it appears to us, that if Xeno- 

 crimts is a good generic form, the other also should be made a 

 new genus. Gl. Harriai is distinguished from Glyptocrinus almost 

 by the same characters as Xenocrinus from Reteocrinus. We 

 further refer Glyptocrinus cognatus Miller, to Reteocrinus. 



a. Glyptockinites. 

 1. GLYPTOCEINUS Hall. 



1847. Hall. Paleont. New York, i, p. 281. 

 1857. Billings. Geol. Surv, Canada, of 1853 to 1856, p. 256. 

 1859. Billings. Ibid., Decade iv, p. 55. 

 1863. Hall. Trans. Albany Inst., iv, p. 202. 

 1873. Meek. Geol. Surv. Ohio Paleont., i, p. 30. 



1879. Zittel. Handb. d. Paleont., i, p. 374 (not Olyptocrinus d'Orb., 1850, 

 Prodr. i, p. 45, nor p. 103). 



Syn. Apiocrinite Anthony, 1838 (not Miller, 1821). 



Syn. leosidactylocrinus Owen, 1843, Cat. Spec. Ohio Valley. 



We are compelled to exclude from the genus Glyptocrinus 

 several species which were referred to it by Hall and Billings, and 

 have arranged them with other genera. We place Glyptocr. 

 Garleyi Hall — which has four basals and not five — under Maria- 

 crinus as reconstructed and amended by us. The generic differ- 

 ences between Glyptocrinus and Glyptaster have never been satis- 

 factorily pointed out, and Hall's explanatory remarks (Trans. 



