On the Monticulipo]oid Corals of the Cincinnati Group. 27 



Corallum hemispheric, rarely globular, eight to ten lines in 

 diameter, from three or four to seven or eight lines high. Surface 

 s:nooth. Calices of two kinds, the larger oval or circular, the 

 iimaller sub-angular, wedged in between the larger ones, occasion- 

 ally aggregated into star-sha[)ed niacula2. Si)iniform corallites 

 numerous. 



var. L.-Kvis Ulrich. 



Monticiilipora Icvvis, Ul. Jour. Cin. Soc. Nat. Hist. V, 236, 

 r882. 



Differs in the cells being generally nearly equal, and polygonal 

 instead of oval or circular. 



var. NEGLECTA, n. var. 



Corallum irregularly conical; surface with many prominent 

 monticules, about one line apart. Calices equal in size, sub-poly- 

 gonal. Corallites take a direct course from base to appex. (Plate i, 



fig- 3)- 



Obs. The type form was regarded, as seen above, by Dr. 

 Nicholson as a variety of ^r/^iMV///. It differs from that, however, in 

 being parasitic, or at least attached. Selwynii was a free form. 

 Variety neglecta differs mainly in possessing conspicuous monticules. 



Formation and Locality. — Lower Silurian, Cincinnati Group, 

 Cincinnati. \\ aynesville, Ohio, &c. 



Group VL Species imitating foreign bodies. 



52 M. CALCEOLA, Miller & Dyer. 



Jour. Cin- S. N. Hist. 1,26, 1878. 



Monticiilipora., {Monotrypa) calccola, M. & D.Nicholson, Genus 

 Monlic. 185, i88r. 



Lcptotrypa calccola, LUrich. Jour. Cin. S. N. Hist., VI, 159, 

 1883. 



Corallum free, of rather small size, helicoid in form, and vary- 

 ing from one line to six: lines in diameter. Surface smooth or cov- 

 ered with low rounded monticules. Interior traversed by a horn 

 shaped cavity lined on the inside by encircling stri^, and varying 

 from one-half a line to more than two lines in diameter. Calices 

 variable in size, polygonal, more or less regularly arranged. Walls 

 thin. 



Obs. — This peculiar species is easily recognized from its shape. 

 It was originally compared to the "shape of a little wooden shoe." 

 In the original description an account of how its form might have 

 arisen is given. The authors suppose it to have begun from an 



