CORALS AND BRYOZOA. 185 



This species most nearly resembles T. (0.) immersa, but may be distinguished 

 by its smaller and more closely disposed cell apertures : from T. (0.) hexagona 

 it differs as follows ; the cell apertures are smaller, the elevations between 

 them are less angular, and do not have a regular row of nodes or granules 

 along the middle ; from T. (0.) subquadrala it is distinguished by the fewer 

 ranges of cell apertures on a branch, their somewhat more regular disposition, 

 the wider and less angular elevations between the cell apertures, and the more 

 irregular disposition of the nodes on the surface. 



Formation and locality. Hamilton group, Railroad station near Genesee, N. Y. 



Teematopora (Orthopora) immersa, n. sp. 



PLATE I. VI, FIG. 11. 



ZoARiDM ramose ; bifurcations infrequent. Cells tubular, arising from the center 

 of the branch. Cell apertures oval, length about .20 mm., width from one-third 

 to one-half the length, disposed in longitudinal rows, alternating and forming 

 oblique transverse rows. Peristomes obsolete. Surface between the longi- 

 tudinal rows of apertures elevated, forming prominent ridges, slightly 

 narrower than the cell apertures ; at the base of each aperture there is a 

 comparatively prominent, conical node, and also a minute shallow pit. 



This species most nearly resembles T. (0.) carinata, but may be distinguished 

 as follows ; the branches are somewhat larger, the ranges of apertures are more 

 numerous, the longitudinal ridges are not so prominent and are somewhat 

 irregular ; the oblique transverse rows of apertures are much more conspicuous 

 than in that species, the transverse space between the apertures is much less 

 depressed : from T. (O.) ornata it is distinguished by its somewhat larger cell 

 apertures, the more prominent longitudinal ridges, the fewer ranges of cell aper- 

 tures on a branch, the more prominent nodes and their more regular disposition ; 

 the oblique transverse rows of apertures are much less conspicuous: from 

 T. (0.) bispinulata by the stronger, more prominent, longitudinal ridges and 

 more irregular disposition of the cell apertures 



Formation and locality. Hamilton group, Darien Centre, Genesee county, N. Y. 



