164 SIXTEENTH REPORT OK THE CABINET OF NAT. HISTORY. 



CONOCEPHALITES WISCONSENSIS. 



PLATE VII, riGS. 39 - 41 ; AND PLATE VIII, FIGS. 22, 23, 24, 27 & 28. 



Crepicephalus? wisconsensis : Owen, Geological Report of Wisconsin, Io-\va and Minnesota, 

 Tab. 1, f. 13. ( The upper figure on the specimen, the lower figure being Dikelo- 

 cephalus granulosus.) 



Compare Dikelocephalus latifrons : Shumahd, Trans. Acad. Sciences of St. Louis, Vol. ii, 



- p. 101. 



Head large. Glabella strong, truncato-conical, moderately convex, 

 sometimes subangular in the middle, width at base nearly equal 

 to the length ; front usually straight, sometimes a little curved ; 

 sides nearly straight and regularly converging : the posterior 

 glabellar furrow oblique, and faintly marked ; the middle one 

 less distinct ; the anterior one sometimes obscurely indicated 

 near the anterior extremity of the glabella. Occipital furrow 

 strongly impressed at the sides, but often faintly marked or 

 scarcely perceptible in the middle. Occipital ring narrow at 

 the sides, wider and inclining backwards in the middle, and 

 rising to the base of a strong elevated spine, which is directed 

 obliquely backwards, and in the course of its length is gently 

 curved. Dorsal furrow well defined, not deep, a little more 

 strongly impressed at the anterior angles of the glabella, and 

 continued in front of the same strength as at the sides. 



Facial suture curving slightly outwards from the frontal margin, 

 and then gently curving towards the glabella at the anterior 

 angle of the palpebral lobe, which is a little forward of the 

 middle glabellar furrow ; thence curving to the base of the eyci 

 it is directed outwards. 



Fixed cheeks narrow, with a narrow posterior limb; the pal- 

 pebral lobe limited by a distinct groove : frontal limb much 

 extended, and gently curving at the sides ; the anterior border, 

 for about one-third or nearly one-half its entire length, longitu- 

 dinally flattened and ascending to the anterior margin, with a 

 wide shallow furrow between it and the posterior gently convex 

 portion of the limb. The shallow frontal furrow and posterior 

 part of the limb are sometimes visibly striated, with flexuous 

 interrupted lines which converge towards the glabella ; and 

 the bottom of the groove, in the cast, is sometimes marked by 

 a row of granules or minute tubercles. 



The wide frontal limb and strong curving spine of the occiptal ring are 

 characteristic features of this species. The glabella approaches in form that 

 of C. lOwenHis ; while the frontal limb of that species is much narrower, and 

 the fi^ed cheeks are wider and more elevated. 



