BRYOZOAN FAUNA OF VINCENTOWN LIMESAND 15 



regularly hexagonal, separated by a furrow ; the mural rim is thin, 



convex, regular; the opesium is large and of the same form as the 



zooecium. There is a large distal septula. The ovicell is very small 



and endozooecial. The ancestrula is elliptical, elongated, with a 



large calcified cryptocyst; its opesium is terminal semielliptical. 



Frequently there are irregular zooecia. Gemmation is little regular. 



Measurements. — 



~ . f^ = 0.55-0.65mm. „ . fZs = 0.7-0.85 mm. 

 Opesium^, „ . Zooecia ^ 7 _ _ 



1 |/o=0.4 mm. |fe = 0.6 mm. 



10 zooecia in 4 square mm. 



Affinities. — This fine species presents some remarkable characters — 

 the large distal septula, the dorsal pellicle very thin or absent, 

 and the irregular gemmation. These characters are found also in 

 Membranipora fulgora Brydone, 1916, from the English Senonian, 

 but here the ovicell is not known and there are large interzooecial 

 avicularia. 



There are 6 ancestrular cells, one of which is incomplete. The 

 irregular cells, quite variable in size, appear to be accessory cells 

 necessitated by the irregularity of the ordinary gemmation on the 

 very uneven substratum. Regenerated cells occur. 



Occurrence. — Vincentown limesand : Vincentown and near Black - 

 woodstown, N.J. (rare). 



Cotypes.— U.S.N.M. Nos. 73861, 73862. 



APLOUSINA DISJUNCTA Gabb and Horn, 1862 



Plate 2, Figures 1-6 



1862. Biflustra disjuncta Gabb and Horn, Journ. Acad. Nat. Scl. Philadelphia, 



ser. 2, vol. 5, p. 162, pi. 20, fig. 50. 

 1907. Biflustra disjuncta Ulkich and Bassler, in Weller, Geol. Surv. New 



Jersey, Paleontology, vol. 4, p. 333, pi. 23, fig. 13 (bibliography). 



Description. — The zoarium is bifoliate, compressed, of dichoto- 

 mous fronds ; the two lamellae back to back are adherent or separa- 

 ble. The zooecia are robust, separated by a little salient thread, 

 elongate-hexagonal in outline, growing in longitudinal series and ar- 

 ranged in quincunx; the cryptocyst is convex, very finely granular 

 and encircles the opesium laterally; the intercellular calcification, 

 often incomplete, occasions a partial or total disjunction. The zoo- 

 ecial walls are independent, cf each other and bear two small 

 uniporous septulae. The opesium is large, terminal elliptical, elon- 

 gated, somewhat variable in form. The ovicell is endozooecial, very 

 little convex and covers simply the distal portion of the opesium. 

 There are regenerated zooecia. 



Measurements . — 



~ . fAo = 0.65 mm. „ . fZs = 0.85 mm. 

 Opesium {, - ot , Zooecia { 7 n ee 



r |fo=0.35 mm. [ fe = 0.55 mm. 



