27S PALAEONTOLOGY OP ILLINOIS. 



It gives us much pleasure to associate the name of Mr. Fuller with 

 the above described species. 



The full complement of plates having been made up prior to the recep- 

 tion of the remarkable specimen discovered by Mr. Fuller., its full 

 illustration has unavoidably been deferred. That of the Iowa specimen, 

 however,with the description, will enable the recognition of other indi- 

 viduals that may hereafter be found. 



Position and locality : Carbonaceous shale overlying coal No. 3? at 

 Bloomington, Illinois, and in the lower portion of the middle Coal Mea- 

 sure, Dallas county, Iowa. 



Cladodus pajntdatus, St. J. and W. 



PI. IV, Fig. 8. 



We here refer to a unique example of a minute form in the Coal 

 Measures, which in general outline and size closely resembles G. Fullcri 

 of the same horizon, from- which, however, it is readily distinguishable 

 by the presence of more numerous lateral denticles. The base is mark- 

 edly sinuous in front, relatively deep, moderately arched downward and 

 inbeveled, produced downward iuto a strong continuous marginal border 

 between the quite prominent anteroinferior angles, broadly rounded at 

 the extremities and posteriorly, inferior surface rather deeply excavated, 

 postero-superior surface moderately eouvex, with an ill-defined basal 

 pad, which apparently stretches across the greater diameter and about 

 midway between the base of the crown and the posterior margin. The 

 median cone is proportionately strong, gradually tapering, very slightly 

 curved sigmoidally, and produced obliquely outward beyond the line 

 vertical to the horizontal plane of the base, compressed in front, broadly 

 rounded behind, with delicate cutting edges; the lateral wings are 

 occupied by an irregularly alternating series of three or four pairs of 

 relatively small denticles, with indications of accessory denticles in front 

 and flanking the large exterior cones, which latter are moderately 

 deflected laterally and recurved, the inner ones more erect, aud similarly 

 ornamented as the median cone, which latter is marked by numerous 

 closely arranged thread-like striae. Greatest hight of tooth about . 19 

 inch, lateral diameter of base . 21. 



The form described is further distinguishable from C.carinatus by the 

 less regular disposition of lateral denticles aud the more numerous and 

 delicate striatiou. The specimen is somewhat worn, but the general 

 characters are well exhibited, and in the light thrown upon the extent 

 of variableness of individual teeth by the remarkable jaw discovered 

 by Mr. Fuller, there would appear to be no doubt as to its specific 

 distiuctuess from C. Fulleri. The form apparently belongs to the sec- 



