BRYOZOA. 497 



(among which I find the lunarium) agrees well with what is 

 found in C. latuw, PI. XLIII, fig. 8, shows the perfect zooecia 

 apertures in C. ci-ibri forme. 



COSCENIUM LATUM Ulrich. 



PI. LXXYI, Fig. 7-7b. 



Zoariuni growing from, an expanded base, attached to foreign 

 bodies, into a flabellate, reticulated frond, from 5 to 10 or 

 more cm. in height and width; consisting of regularly inosculat- 

 ing flattened branches, about one mm. thick and four or five 

 mm. wide. Fenestrules broad oval, 3 or 4 mm. long and 2 to 

 3 wide, arranged in rather regular intersecting series. Margins 

 of fenestrules and basal portion of zoarium noii-celluliferous and 

 very finely granular. Zooecia apertures arranged in regular, 

 curved, diagonally intersecting series, and in less regular trans- 

 verse and longitudinal rows. When the specimens are worn the 

 last arrangement is the most obvious; seven to nine rows be- 

 tween the fenestrules. Apertures when well preserved, with 

 unequally elevated peristome, commonly kidney shaped or sub- 

 pyriform, more rarely, sub-circular, a little larger near the 

 feuestrules than over the central portion of the inosculating 

 branches, varying from 0.15 to 0.25 mm. in diameter on an 

 example in the ordinary state of preservation, six or seven in 

 three mm. measuring diagonally, more than their own diameter 

 apart. Lunarium generally evident, always directed away from 

 the nearest fenestrules. Interspaces solid at the surface, flexu- 

 ously striated or finely granular; internally occupied by vesicu- 

 lar tissue. 



This fine species is the only one known to me from the Low r er 

 Carboniferous rocks. It differs from the Devonian C. cribiforme 

 Prout, it its wider branches and interspaces, the elevated zooecia 

 apertures, and in their obvious diagonal arrangement. 



Position and locality: Burlington limestone: Calhoun Co., 111., 

 Quiucy, 111., and Burlington, Iowa. 



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