NORTH AMERICAN EARLY TERTIARY BRYOZOA. 475 



The recent species of this genus are: 



Mucronella (Lepralia) peachi Johnston, 1847. 



Mucronella (Lepralia) ventricosa Hassall, 1841. 



Mucronella (Lepralia) vanolosa Johnston, 1847. 



Mucronella teres Hincks, 1881. 



Mucronella crozetensis Waters, 1904. 



The known fossil species are : 



Mucronella (Lepralia) horncsi Keuss, 1865. Oligocene of Germany. 



M uc-ronella (Lepralia) grotriani Reuss, 1865. Oligocene of Germany. 



MUCRONELLA PATENS, new species. 



Plate 62, fig. 10. 



Description. The zoarium incrusts shells. The zooecia are distinct, wide, 

 hexagonal ; the frontal is convex, and surrounded by a double row of small areolae, 

 much crowded. The peristome is salient, wide, its proximal portion is a very 

 salient and erect mucro ; the lyrula is small and triangular. The ovicell is hyper- 

 stomial and is placed on the distal zooecium ; it is small, globular, salient, smooth ; 

 its orifice is placed just at- the level of the mucro. 



,, . \/tpe=O.Wmm. . [7.3=0.60-0.70 mm. 



Measurements. Penstomice 7 Zooecia 7 



\lpe=0.15 mm. [fc=0.7o mm. 



Affinities. This species is quite well characterized by its great zooecial width : 

 all the known species have some elongated zooecia. 



Occurrence. Middle Jacksonian (Castle Hayne limestone) : Wilmington, North 

 Carolina (rare). 



Holotype.Czt. No. 64139, U.S.N.M. 



MUCRONELLA GRANULOSA, new species. 



Plate 62, figs. 8, 9. 



Description. The zoarium incrusts bryozoa. The zooecia are distinct, little 

 elongated, hexagonal ; the frontal is convex, surrounded by a line of small areolae 

 and formed by a regularly granular pleurocyst. The peristome is thin, sharp, little 

 salient; it bears on the anter 4 to 6 spines and on the poster a lamellar mucro, 

 oblique, very prominent and partially hiding the apertura ; a small lyrula and two 

 very small cardelles are visible at the base of the peristomie. 



Measurements. Peristomice 



Ae=O.OS mm. . (Z.?=0.51mm. 



Zooecia L 



lpe=O.Umm. ^1^=0.40 mm. 



Affinities. This species is very elegant; it is rather rare that the elements of 

 the pleurocyst are deposited with such regularity ; however, this phenomenon exists 

 in Mucronella variolosa Johnston, 1847. A single specimen has been found, in- 

 complete, for the ovicell is wanting, but it appears interesting to us on account of 

 its elegance alone. 



Occurrence. Lower Jacksonian (Moodys marl) : Jackson, Mississippi (very 

 rare) . 



Holotype.Cat. No. 64138, U.S.N.M. 



