GENUS ILLiENUS. 377 



This species was, I believe, first identified with the European C. insignis 

 by M. E. DeVerneuil, in his memoir on the parallelism of the European 

 and American palaeozoic formations.* A comparison with the figures of 

 Beyrich then satisfied me that our species was identical with the European 

 one, and I expressed this opinion in Vol ii, Pal. N. Y. The species occur- 

 ring in Tennessee, which is probably the same as ours, has been identi- 

 fied by Dr. Rcemer with Ceraurus bimucronatus of Murchison, which he 

 regards as synonymous with Calymene speciosa of Hisinger, not of Dal- 

 MAN. Our species bears as close a resemblance to C. quenstedti and C- 

 ohtusatus of Barrande as it does to C. insignis. 



LICHAS BREVICEPS ? 



PLATE 21 (12), FIGS. 12-14, PAGE 834 (30). 



The specimens figured are a head, which in all important characters cor- 

 responds with L. bj'eviceps as described by me. The pygidium, fig. 14, 

 occurs on the same specimen of rock, and corresponds in size to the head, 

 both figures being enlarged two diameters. 



The pygidium difi'ers from the pygidia associated with the head of 

 L. breviceps in the Waldron locality only in the central posterior indenta- 

 tion, and in this respect corresponds with L. nei'eus, which it otherwise 

 closely resembles. It is therefore unnecessary to propose any other name 

 until we have better material. Figs. 12 and 14 are from Bridgeport, Illinois. 

 The specimen fig. 13 is from Grrafton, Wisconsin, and is represented of 

 the natural size, the terminal portion having been restored to correspond 

 with fig. 14. 



ILL^NUS CUNICULUS (n.s.). 

 PLATE 22 (13), FIG. 12. 



Glabella sub-quadrangular in outline, broadly rounded on the anterior 

 margin, with the edge sharply recurved : general surface regularly 

 convex, a little more arcuate transversely than in a longitudinal direc- 

 tion ; length and breadth very nearly equal. Palpebral lobes moderately 

 elevated, somewhat triangular in form, and laterally produced ; situated 

 very near the occipital border. Suture line reaching the posterior margin 

 of the head, a little within the outer angle of the eye lobe, and slightly 

 indented in front of the eye; thence directed toward the anterior margin 

 with a slightly sigmoid curve : the distance between the sutures on the 

 anterior margin but little less than in front of the eyes. 

 This species, in comparison with /. armatus, I. barriensis and I.imperator, 



has the glabella more elongated, while it is less convex than /. insignis^ 



with shorter, and laterally produced, palpebral lobes. The posterior position 



of the eye lobe is likewise a distinguishing feature. 



* Bulletin Soc. Geol. dc France, 1847. 



lAssem. No. 239.1 48 



