52 CARBONIFEROUS AMMONOIDS OF AMERICA. 



Pkolecanites *? coMPACTUs Meek and Worthen. 

 Plate V, figs. 5-7. 



1865. Goniatites compactus, Meek and Worthen, Proc. Acad. Nat. Sci. Phila., 1865, 



p. 154. 

 1873. Goniatites comjxictm. Meek and Worthen, Geol. Siirv. Illinois, Vol. V, p. 611, 



PI. XXXI, %•. 2a-c. 

 1897. Priorioceran com^actmii , J. P. Smith, Proc. Cal. Acad. Sci., 3d series. Geology, 



Vol. I, No. 3. p. 118. 



The systematic position of this species is somewhat doubtful; the septa 

 are of the Prolecanites type, while the cross section of the whorl retains the 

 Anarcestes shape, approaching that of Gastriocerns. It is evolute, with 

 broad, slightly arched whorls, wide umbilicus, and rounded umbilical 

 shoulder. It may be that this species should be made the type for a new 

 genus of the Prolecanitida?, for the septa are lanceolate, consisting of a long 

 tongue-shaped ventral lobe, flanked by two similar laterals, while the 

 saddles are broadly rounded; but the writer has not seen the original, and 

 is of the opnuon that no one has a right to found genera or species on 

 illustrations alone, of the accuracy of which he has no knowledge. It is 

 barely possible, but not at all likely, that in this case, as in that of Gonia- 

 tites (jreencastlensis, the impressions of the internal septa on the ventral of 

 the next inner whorl give the lanceolate character to the lobes. 



Occurrence and locaUty. — Middle Coal Measures, Menard and ^lacoupin 

 counties, 111. 



Prolecanites greenii Miller. 

 PI. VIII, figs. 4, 5a, 5b. 



1892. Goniatites greenii, S. A. Miller, Advance sheets Eighteenth Ann. Rept. Geol. 



Surv. Indiana, p. 76, PI. X, figs. 5, 6. 

 1894. Goniatites ijh'cnii, S. A. Miller, Eighteenth Ann. Rept. Geol. Surv. Indiana, 



p. 330^ PI. X, tigs. 5, 6. 



Shell minute, discoidal, evolute, volutions more than four in number, 

 narrow, and little embracing. Abdomen narrow and rounded. Cross 

 section of the whorl elliptical. Umbihcus wide and shallow. Septa close 

 and lanceolate, consisting of a short, pointed, tongue-shaped ventral lobe, 

 flanked by two similar laterals. The saddles are rounded and club-shaped. 

 The shape and the septa resemble Prolecanites Jijoni Meek and Worthen, 



