12 KANSAS UNIVERSITY QUARTERLY. 



tersecting series. The reverse surface is smooth. Mesopores and 

 hemisepta apparently absent. 



The systematic position of this genus is somewhat in doubt. The 

 obverse side of the specimens closely resembles that of some species 

 of Rhonibopora, but the zoecial tubes and the form of the zoarium ar& 

 quite different from that genus. It is provisionally referred to the 

 Acanthocladiidpe. 



li/toinhorff((Iia tlelictiUi, n. sp. Plate I, figs. 1-lcZ. 



Zoarium a long, slender compressed stem, dividing dichotomously 

 at distant intervals. Stem subacutely elliptical in cross-section, 0.7 

 to 0.8 mm. wide and 0.4 mm. thick. Zoecia in about eight alternating 

 ranges, also arranged in regularly intersecting series. A^Dertures sub- 

 elliptical, with ridge-like interspaces, giving them the rhombic or 

 hexagonal appearance of the apertures of Rhombopora. Measuring 

 longitudinally, five apertures occur in a space of 2 mm., and four in 

 1 mm. measuring diagonally. Acanthopores of small size present at 

 the cell angles. Reverse side smooth. The primitive portions of 

 the zoecia are usually visible from this side. The specimens usually 

 adhere to the matrix on the obverse side. 



Position and locality : Upper Coal Measures ; Eudora and Law- 

 rence, Kan., and Kansas City, Mo. Type in author's collection. 



Occurs in the lola limestone* (No. 98, Broadhead's Gen. Sect, of 

 the Coal Measure rocks of Missouri) at Kansas City, Mo., associated 

 with the following species: Cystodictya inequimarginata, n. sp., 

 antea ; C. divisa, n. sp., antea ; Fenestella linibata Foerste ; F. remota 

 Foerste ; F. shu/nardl Prout; F. ovaiipora,n. sp., antea ; Polypora 

 subnnarginata Meek; Thaminiscus tenuivamus, n. sp., antea; and 

 Chainodiciyon laxum Foerste. 



University of Kansas, Lawrence, January, 1900. 

 *Haworth and Kirk, this journal, vol. II, p. 109. 



