434 DR F. A. BATHER. 



biserial structure. Stem constant, at the other pole of the long axis ; its proximal region 

 tapering rapidly and composed of low, flanged columnals with wide lumen, its distal 

 region tapering gradually and composed of columnals with a narrower lumen. 



Fam. : Cheirocrinidae. 



§ 283. Diagnosis. — Glyptocystidea in which some plates of Circlet III. are shifted 

 between those of Circlet IV., or conversely, combined with the gradual crowding out 

 of plate 13. Pectinirhombs 14-15 and 12-18 (so characteristic of Echinoencrinidae 

 and Callocystidae) are here suppressed. 



§ 284. The name "Cheirocrinidae" has now been chosen instead of the old-established 

 " Glyptocystidae," so as to avoid confusion with other senses of the latter name, and in 

 particular to render it possible for anyone to follow Prof. Jaekel in transferring 

 Glyptocystis to the Callocystidae without having to alter any Family name. 



§ 285. The divergence in the modifications of the included genera renders it difficult 

 to draw up a diagnosis that shall cover them all. Logically, this would warrant the 

 placing of each genus in a separate Subfamily ; but practically that would merely 

 mean the printing of the names Cheirocrininae, Glyptocystinae, Pleurocystinae, and 

 Cystoblastinae, without any alteration of the generic diagnoses (cf § 280). 



§ 286. Cheirocrinus. 



1856. Cheirocrinus C. E. v. Eichwald, Bull. Soc. Imp. Nat. Moscou, vol. 29, part 1, p. 123. 



Also p. 69 of the separately published reprint, 1857. 



1857. Glyptocystites Bill, (pars), E. Billings, Geol. Surv. Canada, Eep. Progr., 1856, p. 280. 



1857. Glyptocystites Bill, (pars), E. J. Chapman, Canad. Journ., n. ser., vol. 2, p. 303. 



1858. GlyiJtocystites Bill, (pars), E. Billings, Canad. Org. Rem., dec. 3, p. 53. 



1859. Cheirocrinus Eichw., C. E. v. Eichwald, " Lethaea Rossica/' livr. 5, p. 645. 

 1859. Glyptocystites Bill, (pars), J. Hall, "Palaeont., N.Y.," vol. 3, p. 151. 



1874. Glyptocystites Bill., F. Schmidt, Mem. Acad. Sci. Petersbourg, ser. 7, vol. 21, No. 

 11, p. 8. 



1878. Glyptocystis Bill., N. P. Angelin, "Iconogr. Grin. Suec," p. 31. 



1879. Glyptocystites Bill., K. A. Zittel, "Handb. Palaeozool," vol. 1, p. 423. 



1887. Homocystites J. Barrandb, " Echinodermes . . . Extraits du Syst. Silur.," 8vo, pp. 



Also 116, 245. "Syst. Silur. . . . de la Boheme," vol. 7, "Echinodermes, Cystidees," 



pp. 77, 160 (excl. H. tertius). 

 1891. Glyptocystis Bill, (pars), P. H. Carpenter, Journ. Linn. Soc, Zool., vol. 24, pp. 11, 12. 

 1891. Homocystis Barr., P. H. Carpenter, torn, cit., p. 13. 



1896. Homocystis Barr., E. Haeckel, "Amph. und Cyst./' Festschr. Gegenbaur, p. 149. 

 1896. Glyptocystis Bill., E. Haeckel, op. cit., p. 150 (excl. genotype of Glyptocystis). 



1899. Chirocrinus Eichw., 0. Jaekel, "Stammesgesch. d. Pelmat.," vol. 1, p. 212. 



1900. Cheirocrinus Eichw., F. A. Bather, "Treatise on Zoology : Echinoderma," p. 63. 

 1900. Homocystis Barr., F. A. Bather, op. cit., p. 64. 



§ 287. Diagnosis. — A Cheirocrinid with large periproct bounded by plates 7, 8, 12, 

 13, and 14, and filled with small plates; with numerous pectinirhombs, varying in 

 number, but found in all Circlets I.-IV. ; with five subvective grooves radiating from 

 the mouth, between the deltoids, on to the plates of Circlet IV., each groove giving off 



