124 CARBONIFEROUS AM;\I0\0IDS OF AMERICA. 



the flattened sides, narrow abdomen, and the extremely angular lobes. 

 The specimen came from an unknown horizon and locality of the Carbon- 

 iferous of New Mexico, presumably from the Coal Measures. The writer, 

 however, considers this genus as a member of the Glyphioceratidae, from 

 observations made on the young of another species. It probabh' came 

 from Afjanides though Muensteroceras, and in turn gave rise to Bimorpho- 

 ceras by a further division of the external lobes. It seems, however, quite 

 possible that the Bimorphoceras of the Upper Coal Measures, while similar 

 to tliat of the Lower Carboniferous, may not necessarily be of common 

 origin with it. 



Occurrence. — Carboniferous, Coal Measures.? New Mexico, locality 

 unknown. 



GoNiOLOBOCERAs ? LiMATUM Miller and Faber. 



PI. VIII, figs. 8 and 9. 



1892. Goiitatifes IhiiutuK, ^MilliT and Faber, Jour. CiiK-iiiiiati Soc. Nat. Hist.. Vol. 

 XIV, p. Kit). PI. VI, tios. 8 and 9. 



The following description is quoted from Miller and Faber's paper: 



Shell small, elegant, thin, discoidal, rapidly expanding in circumference, with 

 very slio-ht increase in thickness; sides flat, and dorsum faVidomen] narrowly rounded. 

 Umbilicus .small, abrupt, exposing very little of the inner whorls. Volutions 

 expanding dorso-ventrally with very little increase transversely; the outer ones fully 

 embracing the inner ones, flattened on the sides from the umbilicus to the middle 

 of the superior lateral saddles, from which a flat depression extends to the margin of 

 tile rounded dorsum [abdomen]. 



The septa are of the Afianides'iy^e; ventral lol)e linguiform, narrow, 

 twice as long as wide; lateral lobe broad, shallow, and pointed; ventral 

 saddle broader than the ventral lobe and of the same length; superior 

 lateral saddle broader than the ventral saddle, narrow, and rounded at the 

 extremity; second lateral saddle broadly rotmded. Internal septa consist- 

 ing of an antisiphonal lobe and a pair of similar laterals. 



This form is evidently transitional from Agamdes to Goniolohoceras ; 

 it is a typical AganMes on the younger part of tlie shell, but the ventral 

 lobe seems to be divided on the last whorl. 



Occurrence. — Lower Carboniferous, St. Louis stage, Crab Orchard, 

 Ky. Type in the paleontologic collection. Walker iluseum, University of 

 Chicago. 



