GASTRIOCERAS. 85 



1842-4:4. Ammonites listen'. L. (J. <io Koiiinck. I)fs< r. aniiii. fo.ss., ]). 577, PI. LI, 



figs. 4, a-b. 

 1861. G on! at Ites lister!, J. W. Salter, Meui. (ieol. Siii'vi-v, Iron Ores of Great Brit- 

 tain, Pt. Ill, p. 221, PI. I, %s. 35. 36. 

 1863. Gonintiti-s listi-ri (pars), F. Roemer, Zeitschr. Dcutsch. (Jeol. (iesell., Vol. 



XXXVI, p. 213. 

 1884. (rh/phiocfirds carhoiiariuni (i)ai's), A. Hvatt. Pi'oc Boston, Soe. Nat. Hist., 



Vol. XXII, p. 329. 

 18!t(). Goniatites lixteri, J. Ward, Trans. N. Stafls. Inst. Min. and Mocli. Eng., 



Vol. X, PI. I, ligs. 4, 5. 

 1892. Goniatites listeria G. AVild, Trans. Manchester Gcol. Soc., Vol. XXI, p. 396, 



PI. II, figs. 9, in. 

 1896. Gastrioceras, sp. indet., -I. P. Smith, Proc. Am. Philos. Soc. Vol. XXXV, 



p. 262, PI. XX, figs. 1, a, b, c, d. 



1896. Goniatites carhonnrim., H. Bolton, Trans. Manchester Micros. Soc. 1895, 



p. 130, PI. II, fig. 20. 



1897. Gastrioceras carhonariuin, Foord and Crick, Catal. Foss. Ceph. Brit. Mus., 



Pt. Ill, p. 229, tigs. 110, a-d. 



1898. Gastrioceras listeri (par.s), E. Haug, Etudes sur les Goniatites, p. 103. 



1899. Glyphioceras sahcronatum, F. Freeh, Die Steinkohlenformation, PI. XLVI, B, 



figs. 3 and 5. 

 [Not 1840. Goniatites carhmuirius^ ,]. de C. Sowerby, Trans. Geol. Soc. London, 2d 

 series. Vol. V, p. 703, PI. LII, figs. 8, 9.] 



Form somewhat compressed laterally; whorls helmet-shaped, wider 

 than high, highly arched, and indented to nearly one-half the height by 

 the preceding whorl. Greatest breadth at the umbilical margin. Umbil- 

 icus wide and deep, inner area steep. In the adolescent stage the whorls 

 are broad, low, and flattened, with angular sides exactly like those of 

 G. listeri. 



The sides are ornamented with strong tubercles, which on the young 

 stages are like those of G. listeri, but at maturity form ribs tliat reach half- 

 wa)^ up to the abdomen. 



Three or four constrictions are seen on each revolution. Outer shell 

 with fine cross striaj of growth, visible on the cast. The ventral lobes are 

 sharp and narrow, the lateral lobe narrower than is usual with Gastrioceras, 

 and not tongue-shaped. 



The inner whorls are flattened and angular, with much stronger 

 tubercles than those on the mature shell. 



E. Haug" has included not only this species, but also G. coronatmn 



<' Etudes sur lea Goniatites, p. 103. 



