EXPLANATION OF PLATES. 201 



PLATE YIIL 



CONOCEPHALITES MINOR. 



[ Figures four times eulari^ed.] 



Fig. 1. The glabella and fixed cheek. 



«« 2. Profile of the same. 



*« 3. A movable cheek. 



** 4. A pygidium of the same. 



CONOCEPHALITES MINUTUS. 



[ Figures four times enlarged.] 



Fig. 5. Glabella and fixed checks. 

 •« 6. Profile of the same. 

 ** 7. Cheek of the same species. 



CONOCEPHALITES EOS. 



Fig. 8. Glabella and fixed cheeks. 

 <« 9. Profile of the same. 



CONOCEPHALITES lOWENSIS. ( FigS. 10 - 12 & 30.) 



Fig. 10. A small head. The glabella is represented too round in front. See figure 29, 

 Plate vii. 



«« 10 a. Hypostoma of this species. 



«* 11. A cheek of the same species. 



•• 12. A pygidium of the same. 



PtYCHASPIS GRANULOSUS ? ( Fig. 13.) 



Fig. 13. A pygidium, which is of frequent occurrence in slabs containing the head of 

 this species. 

 «< 14. The pygidium of an undetermined Trilobite. 



DiKELOCEPHALUS MISA. ( Fig. 15.) 



Fig. 15. The glabella and fixed cheeks of this species. The glabellar furrows are not 

 properly copied in this figure. See figure 4 of Plate 10. 



CONOCEPHALITES ERYON. ( FigS. 16 & 31.) 



Fig 16. A glabella and fixed cheeks of this species. The glabella is represented too 

 round in front. See fig. 10, Plate vii. 



«« 31. A similar specimen from Lacrosse. The anterior pair of furrows are rarely 

 seen. 



CONOCEPHALITES OWENI. ( FigS. 17 & 20.) 



Fig. 17. A glabella and fixed cheeks. 

 «« 20. A movable cheek from the same specimen in which the head is found. 



CONOCEPHALITES DIADEMATUS. ( FigS. 18 & 21.) 



Fig. 18. The glabella and frontal limb of this species? showing a very narrow space 

 between the former and the elevated portion of the latter. 

 *• 21. A pygidium, associated in the same specimens of stone with the glabella ; 

 from Marine mills. 



[Senate, No. 115.] 26 



