104 F. A. BATHER, CRINOIDEA OF GOTLAND. 



t lic exact shape of x; but that the species is not a Botryocrinite is clear from 

 the shape of the cup and of the stem-ossicles. 



davisanus, S. A. Miller (Poteriocrinus), Journ. Cincinnati Soc. Nat. Hist., vol. for 1882, 

 p. 226. This was referred to Homocrinus by Wachsmuth and Springer in 1886 

 {/oc cit.). The anal plates are said by Mr. Miller to be two or three and small, 

 while Pl. IX, tig. 4 b does not afford more definite information. The character 

 of the arm-branching however, shows that this is neither a Homocrinus nor a 

 Poteriocrinus, but one of the Decadocrinida\ 



dipentas, Eichwald (Homocrinus), Lethaea Rossica, Lief. Y, p. 583, is now referred lo 

 Hoplocrinus dipentas, and one specimen to Baerocrinus Ungerni. 



fusiformis, C. F. Römer (Poteriocrinus), Das Rheinische Uebergangsgebirge, p. 61; 1844. 

 This was retained in Poteriocrinus by don. Muller and L. Schultze, but was 

 referred to Homocrinus by Wachsmuth and Springer in 1879 (op. cit.). Roth 

 Schultze and the latter authors however, consider that Bactrocrinites fusiformis, 

 Sciinur in Steimnger, »Versteinerungen der Eifel», p. 22, 1849, is a synonym 

 of this; and such is no doubt the ease. If then this species were a Homocrinus, 

 the name Bactrocrinus would have three years precedence of Homocrinus. This 

 species, however, does not really seem to be a Homocrinus, since it differs in 

 the pentagonal shape of its stem, the solidity of its tegmen, the small size of its 

 anal tube and the horse-shoe-shape of its radial facets. I prefer therefore to 

 follow Zittel in regarding Bactrocrinus as a separate genus. 



gracilis, Hall (Poteriocrinus), Nat. Hist. N. Y. Palaeont., vol. I, p. 84; 1847. This was 

 referred b}' Hall to Homocrinus (op. cit., vol. II, p. 185; 1852), but was placed 

 in Dendrocrinus by Wachsmuth and Springer in 1879 (Revision I, 76). The 

 generic characters are not clearly shown in the tigurc. 



nanus, C. F. Römer (Poteriocrinus), Palseontographiea, vol. IX, p. 150; 1863. This was 

 referred to Homocrinus by Wachsmuth and Springer in 1879 (Revision I, 78) 

 but was retained in Poteriocrinus by O. Follmax in 1887 (Yerh. nat. Ver. 

 preuss. Rheinl., vol. XLIV, p. 121). The systematic position of this species is 

 still uneertain; the anals have never yet been seen; the arms were described by 

 Römer as bifurcating on the 4th brachial and bearing simple armlets on every 

 8th, 9th or lOth ossiele; the armlets, however, appear to branch, and indeed the 

 whole arm often has a dichotomous appearance. The stem and general shape 

 agree with other species of Homocrinus. 



nettelrothanus, S. A. Miller (Poteriocrinus), Journ. Cincinnati Soc. Nat. Hist., vol. for 

 L882, p. 227. This was referred to Homocrinus by Wachsmuth and Springer 

 in 1886 (Revision, III, p. 220). The anals are unknown, but arm-branching i» 

 of Decadocrinid type, so that the species is probably neither Poteriocrinus nor 

 Homocrinus. 



nucleus, Hall (Dendrocrinus), 28th Rep. N. Y. State Cab. Nat. Hist., first edition Pl XV, 

 figs. 7 — 9; 1876. Referred to Qyathocrinus in 2nd edition p. 136; 1879; and 

 to Homocrinus by Wachsmuth and Springer (Revision, III, p. 220). It is almosl 

 certainly a Botryocrinus. 



