128 



TRILOBITA. 

 Calymene callicephala, Green. 



Galymene rallicephala, Gveen 1832. Monogr. Trilobites N. America, p. 30, 



cast 2. 

 Calymene senaria, MLeek 1873. Geol. Surv. Ohio, Palseont., vol. I., p. 



173, pi. 14, figs. 14, a-f. 

 Galymmene callicephala, Clarke. .1894. Lower Silur. Trilobites Minn., p. 699. 



Lower beds, T. C. Weston, 1884 : the cephalon, minus the free cheeks, 

 of a very small specimen, which is referred to this species with some 

 doubt. It is most probably identical with the species so common in the 

 Hudson River or Cincinnati formation of Ohio, for which, according to 

 Dr. Clarke, the name C. callicephala must be retained, but it may 

 possibly be referable to the C. senaria, Conrad, of the Trenton limestone. 

 Its anterior margin seems to be regularly rounded, rather than shovel 

 shaped. 



Cheirurus Icarus, Billings. 



Oheirurwi Icary£,}iilliags 1859. ■ Canad. Nat. and Geol., vol. V., 



p. 67. 



186.3. Geology of Canada, p. 219, fig. 231. 



OerauruK Icariis, Meek 1873. Geol. Surv. Ohio, Palaeont., vol. I., 



p. 162, pi. 14, figs. 11, a-c. 

 CJieiruru-s Icarioi, (Billings), Whiteaves. .1880. Geol. Surv. Canada, Rep. Progr. 



for 1878-79, p. 50 C. 



Lower beds, Dr. R. Bell, 1879, one pygidium, and T. C. Weston, 1884, 

 two pygidia. 



Encrinurus raricostatus, Walcott. 



EncrinuriK raricostatiis, Walcott 1877. Adv. sheets Thirty-first Reg. 



Rep. N.Y. St. Cab. Nat. Hist., 

 p. 16. 



" 1879. Thirty-first Reg. Rep. N.Y. 



St. Cab. Nat. Hist., p. 69. 

 Safford & Vogdes . . . . 1887. Proc. Acad. Nat. So. Philad., 

 p. 167, fig. 2. 



Lower beds, T. C. Weston, 1884 : one pygidium, and portions of two 

 glabellse that may be referable to this species, which was based upon a 

 pygidium only. 



