On the Species of the Genus Palccoxyris. 59 



may be well to call attention to the closely-allied genus 

 Fayolia, described by Eenault and Zeiller,i from the coal 

 measures of Commentry. This genus is distinguished from 

 Palceoxyris by the presence of a very pronounced, either 

 entire or dentate "collerette" on the sutures of the segments. 

 On the spiral segments is also situated, towards their lower 

 margin, a row of short, stiff, spine-like projections. This 

 genus has also been noted by Weiss as occurring at 

 Alben.2 



Pal^oxyris, Brongniart, emend. 



Annales des Sciences Naturelles, 1^ ser., vol. xv., p. 456. 1828. 



Prodrome, pp. 137 and 190. 1828. 

 CarpoUthes, Morris, Trans. Geol.Soc, London, 2d ser., vol. v., p. 489, and 



Explanation to figures 12 and 12a, pi. xxxviii. 1840. 

 Palceohromelia, Ettingshausen, Abhandl. d. k. k. geol. Reichsanstalt, 1 Band, 



III. Abth., p. 1. 1852. 

 SjJorledcria, Stickler, Die Bromeliaceen der Yorwelt. Berickte d. natur. 



Vereines des Harzes zu Blankenburg. Yernigerode, 1861. 

 S'pirangiu^n, Sckimper, Traite d. paleont. veget., vol. ii., p. 514. 1872. 



Generic description. — Fossils arranged in an umbellate or 

 verticillate manner around a stem (?) or terminating a 

 common peduncle (?). Each individual of the whorl oblong 

 or fusiform, and composed of spirally contorted concave 

 segments, which at their sutures form a slight coUerette. 

 The segments are continued downwards to form a pedicel, 

 and produced upwards into a long beak. When the fossils 

 are compressed, the anterior, crossing obliquely the posterior 

 circumvolutions of the spirally contorted segments, imparts 

 to the surface of the compressed specimen the appearance as 

 of being composed of a number of rhomboidal imbricating 

 scales. 



Bemarks. — Notwithstanding these fossils have been known 

 for over fifty years, our knowledge of their true nature and 

 affinities still remains a hidden secret. Ettingshausen has 

 figured a group of seven individuals springing from a common 



1 Comptes Rendus, 2d June 1884. 



^ Steinkohlen-Calamarien, pt. ii., pp. 152 and 202 (Abbandl. z. geol. 

 Specialkarte von Preussen u. d. Tkuringiscken Staaten, Band v.. Heft 2. 

 Berlin, 1884. 



