120 CARBONIFEROUS AMMOJs^OlDS OF AMERICA. 



MUENSTEROCERAS OWENI Hall. 



PI. XIX, figs. 3-8. 



1860. GoniatUes oweni,.J. Hall, Thirteenth Rept. New York State Cab. Nat. Hist., 



p. 100, tigs. 11, la. 

 1862. Goiiiatites oweni, A. Winchell, Am. Jour. Sci., 2d series. Vol. XXXlII,p. 36-1. 

 1879. GoniatUes momi, J. Hall, Pal. N. Y., Vol. V, Pt. II, p. 17 , PI. LXXIII, figs. 



3-8, PI. LXXIV, fig. 9. 

 1881. GoniatUes oweni, C. A. White, Second Aim. Rept. Geol. Surv. Indiana, 



p. 514, PI. VII, figs. 3 and 4. 

 1884. Muensteroceras oweni, A. Hyatt, Proc. Boston Soc. Nat. Hist., Vol. XXII, 



p. 326. 

 1884. Ihiensteroceras whitei, A. H.yatt, Proc. Boston Soc. Nat. Hist.. Vol. XXII, 



p. 326. 

 1886. GoniatiteK oweni, J. Hall, Fifth Ann. Rept. N. Y. State (leologist, PI. XIII,' 



figs. 4, 7. 

 1888. GoniatUes oweni, C. E. Beecher, Pal. N. Y.. Vol. V. Pt. II. Supplement, 



p. 40, PI. CXXVIII, figs. 4-7. 



1897. Glyphioceras oioeni, Foord and (Irick, Catal. Foss. Ceph. Brit. AIus., Pt. Ill, 



p. 188, fig. 89. 



1898. Pericydus {Muensteroceras) oweni, E. Haug, fitudes sur les Goniatites, p. 102, 



PI. I, fig. 43. 

 1901. Glypliioceras oweni, F. Freeh, Ueber devonische Anmionecn. p. 84, fig. 37a. 



Shell discoidal, laterally compressed, abdomen rounded, sides some- 

 what flattened. Whorl about as high as broad, deeply embracing, covering 

 four-fifths of the inner whorl, and indented by it to one-half of the height. 

 Cross section of the whorl helmet-shaped; height less than one-half of the 

 total diameter; greatest breadth a short distance above the umbilical 

 shoulders, which are abrupt and angular. Umbilicus moderately wide, 

 varying in width from one-fourth to more than one-third of the total 

 diameter, and exposing the angular shoulders of all the inner whorls. The 

 inner whorls are very globose, the breadth at diameter of 10 mm. being 

 nearly equal to the diameter, and the umbilicus is proportionally nar- 

 rower. Surface of the shell, which is rarely seen, marked by fine trans- 

 verse strife. Surface of cast marked by three or four wide and shallow 

 constrictions, beginning on the umbilical shoulders and bending back\A'ard 

 over the abdomen in a broad curve. These constrictions are variable in 

 interval and become much more fi-equent on old shells. 



Septa close together, consisting of a long, narrow siphonal lobe, 

 divided by a short, notched siphonal saddle; a sharply pointed, shallow 



