584 PROCEEDiyClS OF THE NATIONAL MUSEUM. vol. xxvi. 



absence of diaphragms especially, will distinguish it. IT. hibet'culata 

 Ulric'h, from the Black River shales of Minnesota, also has a similar 

 zoarium, but in other respects is quite different. 



Occurrence. — A very abundant and characteristic fossil of the mid- 

 dle division of the Richmond in Ohio and Indiana. James's specimon.s 

 were recorded from Lynchburg, Highland County, Ohio. Other 

 localities are Oxford, Waynesville, and Oregonia in Ohio and Rich- 

 mond, Indiana. 



Cat. Nos. 40224, 40228 Harris collection, 41765, 41766, U.S.N.M. 



HOMOTRYPA \A/^ORTHENI var. INTERCELLATA, new variety. 

 Plate XXIV, fig. 17. 



This seems to be a constant and well-marked variety, agreeing with 

 H. wortheni in its general zoarial characters, but differing in having 

 the walls more crinkled in the axial region and an abundance of meso- 

 pores and small acanthopores in the peripheral. Viewed under a lens, 

 the zooecia at the svirface with the numerous mesopores and small 

 acanthopores resemble those of IloinotrypeUa., but otherwise the struc- 

 ture is that of Hornotrypa. 



Occurrence. — Abundant in the Richmond near Osgood and near 

 Versailles, Indiana. 



Cat. Nos. 41768, 41769, U.S.N.M. 



HOMOTRYPA WORTHENI var. PROMINENS, new variety. 

 Plate XXIV, figs, 15, 16. 



The very prominent, elongated monticules will distinguish this 

 variety. The zoarium also differs from the cylindrical branches ol 

 II. wortheni by forming broader, subcompressed to flat fronds. 

 Internally this variety and species are practically identical. 



Occurrence. — Abundant in the highest bed.s of the Richmond alon^ 

 Elkhorn Creek near Richmond, Indiana. 



Cat. No. 41767, U.S.N.M. 



HOMOTRYPA AUSTINI, new species. 



Plate XXIV, ligs. 5-9. 



The branches of this neat species are small, cylindrical, 4 to S mm 

 in diameter, and divide rather frequently. Surface smooth. Zo(ccii 

 small, polygonal to rounded, thick walled, nine to ten in 2 mm 

 Acanthopores numerous, four or more often surrounding a zowciuD 

 and generally visible at the surface as blunt spines. Mesopores 

 except an occasional one in the macula?, wanting. The zooecia in th 

 axial region are without diaphragms and have thin, crinkled walls, th 

 greatest amount of crinkling occurring just l)efore the periphera 



