PKOLECANITES. 53 



l)ut ill r. fircenii, the ventral lobe; is broader and dart-shaped, wliile in 

 /'. hioiii it is simply a blunt point. 



Occurrence. — Lower Carboniferous, Kinderhook, New Albany, lud. 



Prolecanites gurleyi Sniitli, sp. nov. 



PL XXIV, fio-s. 1-4. 



Shell extremely evolute, laterally compressed, widely umbilicate. 

 Whorls low, and increasing very slowly in height, little embracing, and 

 scarcely indented by the inner volutions. The umbilicus is wide and shallow. 

 The cross section of the whorl is quadrate oval, the curve being interrupted 

 by the rounded abdominal shoulders. The height of the whorl is one-fourth 

 of the total diameter, and the breadth is slightly greater than the height. 

 The width of the umbilicus is one-fourth of the total diameter of the shell. 

 Six volutions are seen at the diameter of 16 mm. 



The surface of the cast is entirely smooth, none of the outer shell being- 

 preserved. The length of the body chamber is unknown, as the only 

 specimen seen is septate to the end. The septa are spatulate, the ventral 

 lobe is undivided and tongue-shaped; the first lateral lobe is similar, and 

 of the same size; the second lateral is two-thirds of the length of the first, 

 and similar in shape. There is a short auxiliary lobe on the umbilical slope. 



This species is most nearly related to Prolecanites (jreenii Mille-r, but 

 differs from it in the greater evolution, wider umbilicus, less compressed 

 whorls, and slower increase in size. 



Occurrence. — Lower Carboniferous, Kinderhook stage. Cedar (iap, 

 Wright Count}', Mo. The type specimen. No. 8600, paleontologic collec- 

 tion. Walker ]\Iuseum, University of Chicago, was loaned to the writer by 

 Dr. Stuart Weller. The specific name is given in honor of Prof. W. F. E. 

 Grurley. 



Prolecanites houghtoni Winchell. 



1862. Qoniatites houghtoni, A. ^\'iucllL■ll, Am. Jour. Sci., 2d series, Vol. XXXIII, 

 p. '363. 



Shell discoidal, evolute; whorls but slightly embracing, with flattened 

 venters and sides, and cross section elongate-oval. Umbilicus wide and 

 shallow. Surface smooth. Septa lanceolate, with pointed tongue-shaped 

 lobes and rounded saddles; an undivided ventral lobe, two principal and 

 an auxiliary lateral lobe. 



