PRODROMITES, A NEW AMMONITE GENUS 26 1 



2. Specimen obtained from Professor G. C. Broadhead, Chouteau lime- 

 stone, Pettis county, Missouri, probably from the same locality as the last. 

 No. 6474, Paleontological Collection, Walker Museum, University of 

 Chicago. 



DIMENSIONS 



Diameter - 1 iy mm 



Height of last whorl - - 68 



Height of last whorl from the preceding - 38 



Width of last whorl - 



Involution - - 30 



Width of umbilicus - 5 ? 



3. Specimen from the Kinderhook limestone of Burlington, la., near the 

 top of the Kinderhook Series as exposed at that locality. No. 6222, Paleon- 

 tological Collection, Walker Museum, University of Chicago. 



DIMENSIONS 



Diameter - - - 75""" 



Height of last whorl - - - 42 



Height of last whorl from the preceding - 25 



Width of last whorl - - 10 



Involution ------ 17 



Width of umbilicus about - - 4 



4. Specimen from the Kinderhook goniatite limestone of Rockford, Ind.; 

 in the paleontological collection of Fred. Braun, of Brooklyn, N. Y., where it 

 was examined by the writers. Its dimensions are about the same as of the 

 two specimens from Missouri. 



Prodromites praematurus sp. now, Smith and Weller. Plate 

 VIII, Figs. 3, 4 - 



Type is specimen, No. 6223, Paleontological Collection, Walker Museum, 

 University of Chicago. Form laterally compressed, discoidal, involute, deeply 

 embracing, with narrow umbilicus, narrow slightly flattened abdomen sur- 

 mounted by a hollow keel three millimeters high. Whorl indented by the 

 preceding whorl to a little over one third of its height. Surface smooth, so 

 far as known. 



The septa are complex, ceratitic, with rounded entire saddles, serrated 

 lateral lobes, and a series of auxiliaries above the umbilicus. The ventral 

 lobe is narrow, and undivided ; the first lateral is longer, and three pointed ; 

 the second lateral, four-pointed ; the third lateral, bifid ; the fourth lateral, 

 bifid, but more deeply so than the third ; then begins a series of auxiliary 

 lobes, undivided and pointed, seven in number. 



