BRYOZOAN FAUNA OF VINCENTOWN LIMESAND 77 



angular and acuminated. On the short zooecia the two lateral avicu- 

 laria placed above the ascopore unite to the preceding and form a 

 3-pored lip on the peristomice. When the proximal avicularium is 

 transformed into a large frontal one, the two small lateral avicularia 

 placed below the ascopore disappear. Thus the symmetrical arrange- 

 ment of the avicularia is frequently deranged. 



The diameter of the branches varies from 0.5 mm to 1 mm. 



Affinities.— Ulrich and Bassler, 1907, believed that this species rep- 

 resented Gabb and Horn's Entalophora quadrcmgularis (see pi. 10, 

 p. 58) upon the assumption that their figure, although quite different, 

 could if based on a Vincentown species, apply only to this one. 

 Since the discovery of Ochetosella jacksonica Canu and Bassler, 

 1917, in the Eocene (Jacksonian) of the Atlantic and Southern 

 States they are convinced that Gabb and Horn more likely had an 

 example of that species before them. Beisselina mortoni is well char- 

 acterized by the avicularian mucron, which is very constant. It 

 differs from B.mucronata Canu, 1929, from the French Maastrichtian 

 in its shorter zooecia and in the presence of 6 instead of 3 frontal 

 avicularia. 



Occurrence. — Vincentown limesand : Rare at Vincentown and near 

 Blackwoodstown, N.J. 



Cotypes.— U.S.N.M. No. 52614. 



BEISSELINA LONSDALEI, new species 



Plate 18, Figure 4 



1907. Acropora coronata (not Reuss) Ulrich and Bassler, in Weller, Geol. 

 Surv. New Jersey, Paleontology, vol. 4, p. 351, pi. 26, fig. 11. 



Description. — The zoarium is large, free, bilamellar with the 

 lamellae placed back to back, opposed, and inseparable; the fronds 

 are wide, thick, elliptical in section, branching dichotomously on the 

 same plane. The zooecia are indistinct, elongated, arranged in quin- 

 cunx; the frontal is hidden under the avicularia exteriorly visible; 

 it bears an ascopore at some distance from the aperture and open- 

 ing in the interior of the zooecium below the operculum. The aper- 

 ture is subcircular and hidden at the bottom of a long, little oblique 

 peristomie; the latter is formed by the frontal avicularia in which 

 the walls are very thick, by a salient peristome, and by the peri- 

 stomial avicularia ; the peristomice is orbicular, large, surrounded by 

 4 or 5 small avicularia with or without a pivot and arranged crown- 

 like. The ovicell is hidden under the frontal avicularia. Each 

 frontaj. is covered by four to eight small avicularia with very thick 

 walls, without pivot and irregularly arranged. Frequently the 

 small proximal avicularium develops so much that it forms a large 

 special avicularium covering the entire frontal; it has a pivot, is 



