REPORT ON THE CRINOIDEA. 



301 



1775. Isis asterias, Miiller, Linne's Natursystem, nacli der zwulflen lateinisclien Ausgahe, Niirnberg, 1775, 



Bd. ii. p. 742. 

 1788. Isis asteria, Linnfeus, Systema Naturte, ed. xiii., cura, J. F. Gmelin, Lipsia;, 1788, t. i. pars vi. p. 3794. 

 1816. Encrimis capiit-Mediisw, Lamarck, Histoire Naturelle des Animaux sans Vertobres, t. ii., Paris, 181G, 



p. 435. 



1820. Pentacrinites vulgaris, von Sclilotheim, Die Petrefactenkunde, Gotlia, 1820, p. 327. 



1821. Pentacrinus Caput-Medusm, Miller (pars), A Natural History of the Crinoidea, Bristol, 1821, p. 48, pi. i. 

 1834. Encrinus caput-Medusm, de Blainville, Manuel dActinologie, Paris, 1834, p. 254. 



1836. Pentacrinus Caput-MedusK, Buckland, Geology and Mineralogy, London, 1836, p. 432, pi. 52, fig. 1. 

 1843. Pentacrinus caput- Afedtisce, Miiller (pars), Abhandl. d. k. Akad. d- "Wiss. Berlin, Jahrg. 1841, 



p. 9, Taf. 1. 

 1845. Pentacrinus Caput-iMedusa-, Austin i (pars), A Monograph on Recent and Fossil Crinoidea, Bristol, 



1843-45, p. Ill, pi. 14. 

 1856. Pentacrimis caput-Medusm, Oersted, Forhandl. Skand. Naturf., 7^' Mode i Christiania, 1856, p. 202. 

 1862. Pentacrinus caput-Medusce, Dujardin and Hup^, Hist. Nat. des Zoophytes, Echinodernies, Paris, 1862, 



p. 181. 

 1864. Cenoeriyius Caput-Medusa;, Wyville Thomson, The Intellectual Observer, August 1864, p. 3. 



1864. Pentacrinus asteria^ Liitken, Vidensk. Meddel. f. d. nat. Foren. i Kj0beuhavn, 1864, p. 207. 



1865. Pentacrimis {Neocrinits) asterias, Wyville Thomson, PhiL Trans., vol. civ., 1865, p. 542. 



1872. Pentacrimis asteria, Wyville Thomson, Proc. Eoy. See. Edin., vol. vii. p. 765; and The Depths of the 



Sea, p. 435. 

 1877. Pentacrinus asteria, Wyville Thomson, The Atlantic, London, 1877, vol. ii. pp. 123-126. 

 1882. Pentacrinus asteria, P. H. Carpenter, Bull. Mus. Comp. Zool., vol. x. p. 168. 



Dimensions. 



Length of stem to twentieth node. 



Greatest diameter of stem. 



Longest cirrus (fifty joints), 



Diameter of calyx across first radials, 



Diameter of disk, 



Length of arm (one hundred joints). 



Length of distichal pinnule (twenty-five joints), 



Length of first pinnule after tertiary axQIary (tb' 



rteen joints), 



Stem long, robust, and generally smooth. Outline pentagonal, with slightly rounded 

 angles, but more circular in the lower part. luternodal joints thirteen to twenty-one 

 (usually fifteen to eighteen) in number, with but slightly crenulated edges even in the 

 upper part of the stem. Nodal joints marked by large, transversely oval cirrus-sockets, 

 which occupy almost their whole height. The sockets have sharp, well defined rims, and 

 are entirely filled by the articular facets. Cirri composed of thirty-five to fifty stout, 

 smooth, and tolerably equal joints, with a small terminal claw and no opposing spine ; 

 though the ventral surface of the later joints is often marked by two or three blunt points. 



Infra-nodal joints rarely grooved to receive the cirrus-bases, and then but slightly so. 

 Lowest limit of the interartieular pores between the ninth and twelfth nodes. 



1 The Messrs. Austin and also Dujardin and Hupe give an undated reference to Farm's Hist. Nat. Havannw 

 p. 191, pi. 70, in which this type seems to have been mentioned by the name Palma animal. But I have been unable 

 to consult the work, and can therefore do no more than make this reference to it. 



