64 Field Museum of Natural History — Geology, Vol. IV. 



presence or absence of genal spines would not be of generic importance, 

 the fact that the glabella is divided longitudinally into three lobes 

 appears to be ample reason for separating the American from the 

 European species genetically. This is the character which distin- 

 guishes Chasmops from Dalmanites and the various genera of the 

 Lichadae are based on the variations of the glabella furrows. 



Of the eleven European species of Cybele known to the writer, two 

 have only the pygidium described or figured; the other nine all have 

 well-marked lateral glabella furro vs. Three of these species described 

 by Schmitz, viz., C. grewingki, C. kutorgce and C. revaliensis , exhibit a 

 tendency toward the American forms. The lateral furrows are sep- 

 arated from the dorsal furrows by a narrow lateral margin of the gla- 

 bella, but there are no traces of longitudinal glabella furrows. 



The bibliography of the genus is as follows : 



Cybeloides ella Narraway and Raymond. 



1906 Cybele ella N. & R., Ann. Carnegie Mus., Vol. 3, No. 4, p. 

 598, fig. 1. Black River, Ottawa, Canada. 



Cybeloides iowensis Slocom, genotype this paper. Lower Maquoketa, 

 Iowa. 



Cybeloides prima Raymond. 



1905 Glaphurus primus Raymond, Ann. Carnegie Mus., Vol. 3, 

 No. 2, p. 362, pi. 14, figs. 7-8. 



1905 Cybele valcourensis Raymond, ibid p. 362, pi. 14, fig. 9. 



1 906 Cybele prima Narraway and Raymond, Ann. Carnegie Mus. , 



Vol 3, No. 4, p. 601. Chazy, N. Y. 

 Cybeloides ? winchelli Clarke. 



1897 Cybele winchelli Clarke, Pal. Minn., Vol. 3, pt. 2, p. 742, 

 fig. 59. Galena Limestone, Minn. 

 Cybeloides ? sp. ? Ruedemann. 



1901 Cybele sp. ? Ruedemann, N. Y. St. Mus. Bull. 49, p. 66, pi. 

 4, fig. 12. Trenton, N. Y. 

 The last two species are placed in the genus provisionally until the 

 characters of the glabella are known. 



Cybeloides iowensis sp. nov. Plate XVI, Figs. 1-4. 



Type specimens Nos. P 16631, 16633 an d I 7°39 Field Museum. 



Body depressed convex, distinctly tiilobed, outline, aside from the 

 spines, subovate, tapering rather rapidly to a small pygidium. Surface 

 finely granular with many more or less prominent rounded nodes. 



Cephalon short, width nearly three times the length, outline sub- 

 lunate with the anterior lateral margins inflated. Glabella convex, 

 inflated anteriorly, somewhat longer than wide, widest across the 



