CORALS AND BRYOZOA. 131 



e. Forms in which the carine of adjacent branches, on the celluliferous side, are connected 



by transverse scala. 



UNITRYPA, s. G., Hall. 1885. 



(See page 54.) 



Fenestella (Unitrypa) acaulis. 



PLATE LI, FIGS. 1-6. 



Fenestella (Hemitrypa) acavZit, Hall. Trans. Albany Institute, vol. x, abstract, p. 33. 1881. 



" ( Unitrypa) " " Report of State Geologist for 1885, advance sheets. Expl. pi. 51, 



figs. 1-6. 1886. 

 Unitrypa conferta, Ulbich. Cont. Am. Pal., vol. i, No. 1, p. 17, pi. 1, figs. 8, 8a. 1886. 



Bryozoum infundibuliform, compact. Branches slender, width above a bifur- 

 cation .20 to .24 mm., increasing to from .35 to .50 mm., the strength 

 varying on different fronds, straight, angular when well preserved, 

 rounded when worn, sometimes smooth, at other times nodose; nodes irregu- 

 larly disposed, or in one or more longitudinal lines. Interstices usually 

 narrower than the branches, but on some fronds wider. Dissepiments slender, 

 width from .20 to .25 mm., angular or rounded, on the same plane or elevated 

 above the branches, sometimes continuing across and coalescing with those 

 of adjacent branches, forming irregular, continuous transverse elevations 

 more prominent than the branches, about eight in the space of 5.50 mm. 

 Fenestrules oval, length .40 to .50 mm., width usually from .20 to .25 mm., 

 but on some fronds occasionally .35 mm. 



On the celluliferous face the dissepiments are rounded, very much depressed. 

 Fenestrules narrower than on opposite face, length often three times the 

 width. Cell apertures in two ranges, opening directly outward, oblique to 

 the axis of the branch, twenty-four in the space of 5 mm., separated by less 

 than one-half the diameter of an aperture : margins elevated, strongly in- 

 denting the borders of the fenestrule, those of adjacent branches sometimes 

 nearly in contact. Surface between ranges of apertures carinated ; carinse 

 .50 mm. in height, very thin below, expanding to a width of about .15 

 mm.; carinaB connected by scalae, the summits of which have a width of 

 about .14 mm.; these extend downward till within a short distance of the 

 branch, for half the distance obliquely toward the base, then abruptly bending 



