100 CARBONIFEROUS AMMONOIDS OF AMERICA. 



Worthen, but the septa of the Texan form have each one more lobe and saddle 

 between the j^eriphevy and the margin of the umbilicus than have those of the other 

 form. 



There can be little doubt that this species is correctly referred to 

 Paralegoceras, because the auxiliary lobe appears to be on the umbilical 

 border giving the right number of lobes, although it is not shown in 

 the drawing. 



Occurrence. — Permian, Wichita formation, military crossing of the 

 Big Wichita River, Baylor County, Tex. 



Deposited in U. S. National Museum. 



Paralegoceras iowense Meek and Worthen. 

 PI. IV, figs. 12-14; PI. IX, ligs. 4-7. 



1860. Goniatites iotomsk, Meek and Worthen, Proc. Acad. Nat. Sci. Phila.. 18(30, 



p. 471. 

 1866. Gonidtites ioioensis, Meek and Worthen, Geol. Surv. Illinois, Vol. II, p. 392, 



PI. XXX, figs. 3 a-c. 

 1884. Paralegoceras ioioeme, A. Hyatt, Proc. Boston Soc. Nat. Hist., Vol. XXII, 



p. 327. 

 1893. Paralegoceras iowense, A. Hyatt, Fourth Ann. Rept. Geol. Surv. Texas, p. 474, 



figs. 52-54. 

 Not 1896. Parahyoceras Unuense, J. P. Smith, Proc. Am. Philos. Soc, Vol. XXXV, 

 p. 263, PI. XIX, figs. 1-3. 



The following description is quoted from ^leek and Worthen, in 



Geological Survey of Illinois, Vol. II, p. 392: 



Shell attaining a rather large size, discoidal or nearly flat on the sides, and 

 narrowly rounded on the dorsum [abdomen]. Umbilical rather shallow, about one- 

 half as wide as the breadth of the outer whorl from the ventral to the dorsal side, 

 showing apparently about one-third of each inner whorl. Volutions increasing 

 gradually in size, but gently convex on the sides, nearly twice as l»road from the 

 ventral to the dorsal side as the transverse diameter, and profoundly grooved within 

 for the reception of the inner whorls; aperture, as near as can be determined from 

 a section of the whorls, narrow-sixbovate, deeply sinuous on the ventral side. 

 (Surface unknown.) 



The septa are lanceolate, lobes and saddles all long, narrow, and 

 crowded. Saddles rounded and tongue-shaped, lobes lanceolate and sharph' 

 pointed. The ventral lobe is divided by a siphonal saddle ; the first and 

 second lateral lobes are smaller than the ventral; a fourth lobe lies just on 

 the umbilical border. There are therefore eight lobes visible on the outside. 



