68 PROCEEDINGS OF THE ACADEMY OP [1886. 



CYRTIDOCRINUS Angl., Rev. i, p. 145. 



Cyrtidocrinus was placed by xis among the " imperfectly known 

 genera," but should be referred to the Ichthyocrinidse, as it is 

 closely allied to Lecanocrinus, from which it differs only in having 

 four in place of three underbasals. Like that genus it has a small, 

 quadrangular azygous piece, placed obtusel}^ against the posterior" 

 basal, and between it and the right posterolateral radial. The 

 upper radials are extremely narrow. 



The only known species is Cyrtidocrinus fascietatus Angelin. 



PYCNOSACCUS Angl., Rev. i, p. 41. 



MESPILOCRINUS De Kon and Leh., Rev. i, p. 41. 



TAXOCEINUS Phill., Rev. i, p. 4.3. 



Additional species : 



*1884. Taxocrinus Beyrichi (Dewalque MS.) Fraipont, Zeacrinus Beyrichi ; Extr. 

 des Ann. de la Soc. G^ol. de Belg., Tome xi, p. 112, PI. 1, fig. 5. Dev. supe- 

 rieur. Senzeille, France. 

 1882. T. curtus Williams, Proc. Acad. Nat. Sci. Phi.'a., p. 30. Portage group. 

 Ithaca, N. Y. 

 *1856. T. elegans (Billings), Lecanocrinus elegans Rep. gfeol. Surv. Canada, p. 278; 

 also 1859, Decade iv, p. 47, pi. 4, fig. 4 a h. Trenton limest. City of Ottawa, 

 Can. We consider this species, and also Lecanocrinus laevis E. Billings, to 

 be Taxocrinus. They evidently possess no azygous plate, as they should 

 have if they belonged to Lecanocrinus. 

 Taxocriaus Egertoni ( Poteriocrinus Egertoni Phill. ^= Cladocrinus Eger- 

 toni Aust.), Rev. i, p. 48, is probably an Onychoorinus having 6-7 radials. 

 1882. Taxocr. Fletcheri, Bull, i, Illinois St. Mus. Nat. Hist., p. 31 ; also Geol. Rep. 



Illinois vii, p. 308, PI. 30, fig. 2. Kinderhook gr. Marshall Co., Iowa. 

 1882. T. ithacensis Williams, Proc. Acad. Nat. Sci. Phila., p. 29, PI. 1, fig. 10. 

 Portage gr. Ithaca, N. Y. 

 *1856. T. laevis (E. Billings), Lecanocrinus laevis, Rep. Geol. Surv. Canada, p. 278; 

 also 1859, Decade iv, p. 47, PI. 4, fig, 3 . Trenton limestone. City of 

 Ottawa, Can. 

 *1836. T. nobilis (Phill.), Poteriocrinus nohilis Geol. Yorkshire, p. 205, PI. 3, fig. 

 40. This species has been regarded by some authorities as identical with 

 Forbesiocrinus nobilis De Kon. and Lehon ; but is in our opinion not 

 only specifically distinct, but in all probability a Taxocrinus. Mountain 

 limest. Bolland, Engl. 

 1852. T. oligoptylus (Pacht.). Dimerocrinus oligoptylus Beitr., x. Kenntniss der 

 Gattung Dimerocrinus, St. Peter^^burg, p. 8, with 3 plates. Devonian. 

 Costijitsi, Russia. 

 Syn. Dimerocrinus aptilis Pacht. 



N. B. Taxocrinus priscus (Schnur.) Steinninger, 1853, Geogr. 

 Beschr, d. Eifel, p. 37, is not sufficiently defined for identification. 



