54 Trof. T. Rupert Jones — Fossil Estherice. 



Some of the radials at their intersections of the lines of growth 

 retain thin brownish relics of the test ; but otherwise the valves are 

 represented by partial moulds and casts, much flattened. 



Both come from the Lower Buntersandstein of Diirrenberg, 

 Saxony. 



The specimens figured were courteously lent by the Director of 

 the Geological Survey ^ at Berlin, at the instance of the late lamented 

 Prof. Dr. Ch. E. Weiss, who also gave me some other specimens, 

 collected by himself at Diirrenberg on the road to the Amtsberg, 

 May, 1875. 



6. EsTHEKTELLA NODocosTATA (Giebel), 1857. PI. II. Eigs. 11, 13. 



Posidonotm/a nodocostata, Giebel. Zeitsch. gesammt. Wissensch. Halle, 1857, 



p. 309, pi. ii. fig. 7. 

 Mtheria ? nodocostata, Alberti. Ueberblick Trias, etc. 1864. p. 193, note. 

 Estheria [Estheriella) lineata, "Weiss. Zeitsch. D. g. Gesellsch. vol. xxvi. 1875, 



p. 711, note. 



Fig. 11. — Length 4-2 (hinge-line 2-7), height 2-5 mm. 

 Fig. 13. „ 3-5 ( ,, 2-3), „ 2-4 mm. 



Valves like those of the foregoing species, ovate-oblong in shape, 

 with long, straight dorsal border ; umbo quite forward ; postero- 

 dorsal angle usually pronounced ; ends well rounded ; the posterior 

 curve larger than the anterior ; ventral border gently .curved. 

 Concentric lines numerous and rather feeble. Eadial riblets few 

 (about 9), but much stronger than in E. costata, being definitely 

 raised ridge-like wrinkles wide apart (Figs. 11 and 13). On the 

 inside of the valve (Figs. 13 a, 6) there is a little pit wherever the 

 radial crosses a concentric stria, as if the edges of the successive 

 laminae of the test had been slightly raised just there, so as to leave 

 a little hollow below. The specific name applied by Giebel to this 

 form evidently has reference to this feature, as seen in Fig. 13 a. 

 Locality and collection the same as mentioned with the foregoing 

 species. 



To make the history of the two foregoing species complete, the 

 following extracts are taken from the published memoirs concern- 

 ing them. 



1857. Ch. G. Giebel, Palseont. Untersuchungen ; Zeitschrift fiir 

 die gesammten Naturwissenschaften, Halle, 1857, October u. 

 November, Nos. x. xi. pp. 301-318. 



Posidonomyoe \^EstherioB'] in the Bunter Sandstone near Diirrenberg, 

 p. 308, pi. ii. figs. 6 and 7. 



P. Werigensis, p. 308, pi. ii. fig. 6. Gr. Miinster, Beit. Petrefkd. 

 iv. p. 23, pi. 16, fig. 12. Not far from P. minuta, but with fine 

 radial lines from umbo to border. Wissmann has not noted this [?] ; 

 but it is conspicuous as a characteristic [none given in fig. 6 ; nor 

 is the size mentioned]. [Some true Fosidonomyce are then compared.] 



P. nodocostata, n. sp., p. 309 (fig. 7), as the other species may be 

 1 Konigl. geol. Landesanstalt und Bergakademie, Invaliden Str. 44, Berlin. 



