BRYOZOA. 665 



The conical form of the zoarium distinguishes this form from 

 all the Lower Carboniferous Bryozoa, known to me, except- 

 ing the next described. 



I am indebted to Mr. J. M. Nickles for the only specimens 

 seen of this species. 



Position and locality: St. Louis group; Fountain Creek, Mon- 

 roe county, Illinois. 



QELOCONUS GRANOSTJS Ulrich. 



PL LXXIL Fig. *-3b. 



Zoarium elongate cone-shaped, hollow, with a rather thick, 

 transversely striated epithecal lining, apparently perforated by 

 minute tubuli. Thickness of entire zoarial crust about 0.3 mm. 

 Cone from 8 to 12 mm. long, and from 1.3 to 2 mm. wide 

 across the open top. Base attenuate, usually deflected a little 

 to one side. Zooecia arranged as in C. rhombicus, but with the 

 interspaces higher, granulose, and the summit more rounded; 

 the area more abruptly impressed, deeper, and not so sharply 

 outlined, appearing, in the lower two-thirds of the zoarium, to 

 be rather of oval shape than rhombic. Apertures varying from 

 oval to sub-circular, 0.1 mm. in diameter; measuring longitudi- 

 nally, there are between six and seven in 2 mm.; diagonally' 

 between four and five in 1 mm.; transversely, five and often six 

 in 1 mm. 



Of internal characters, the most striking is the strength of 

 the basal lamina and zooecia walls when compared with C. 

 rhombicus. 



Position and locality: Chester group; near Anna, Union Co., 

 111. 



STREBLOTRYPA Ulrich. 



Acanthoclema Hall (pars). Pal. N. T., voL VI, 1887. 



(For generic diagnosis see page 403.) 



In its superficial characters the typical species of this genus 

 greatly resembles species of D'Orbigny's Cavea (C. costata, et 

 regularis) ,but whether this resemblance is due to real relation- 

 ship, or is only incidental, remains to be seen. Compared with 

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