APR 28 



J 903 



Kansas Dniversity 



Vol. I, No. 10. 



NOVEMBER, 1902. 



Bulletin. 



\ Whole Skim bs, 

 / VOL. XI, No. LO. 



SOME NEW AMERICAN SPECIES OF CYCLUS FROM THE 



COAL MEASURES. 



BY AUSTIN F. ROGERS. 

 With Plate XIV. 



The xipliosuran genus Cyclus, founded upon Agnostusf radialis 

 Phillips, by De Koninck, in 1841, is now represented by fourteen 

 European species — eleven from the Coal Measures of Great Britain, 

 (one species of which is also known from Belgium), one from the 

 Permian of Sicily, and two from the Muschelkalk (Triassic) of Ger- 

 many. A single American species, C. americanus Packard, has been 

 described from the Lower Coal Measures of Mazon creek, Illinois, 

 and as far as can be learned this is the only occurrence mentioned of 

 the genus in this country. 



During the past few years the writer has collected from the Upper 

 Coal Measure limestones of western Missouri and eastern Kansas a 

 considerable number of specimens of this interesting genus which are 

 referred to five new species herein described. They occur for the 

 most part in the Iola limestone* at Kansas City, Mo., associated with 

 typical Coal Measure fossils, f 



Of especial interest is the discovery of the compound eye in Cyclus. 

 This I have found in several specimens of one of the species, Cyclus 

 '■om munis, n. sp., jyostea. It is rather large, oval or elliptical in shape, 

 and is situated near the anterior lateral border (see figure la). In 

 one specimen the facets are, with the aid of a compound microscope, 

 plainly seen to be hexagonal in outline and greatly resembling those 

 of a trilobite. The simple eye (sometimes stalked) has been noted 

 by Woodward and other observers, but as far as can be learned this 

 is the first mention of a compound eye. 



*No. 98, Broadhead's Gen. Sect. Coal Meas. Rocks of Missouri. 



fFor a full list of the fossils of this limestone, see a paper by the, author, "Coal Measure 

 Faunal Studies, I," this journal, vol. IX, pp. 245-247, 1900. 



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