330 CRETACEOUS PALEONTOEOGY. 



1868. Plustrella capistrata Con., Cook's Geol. N. J., p. 723. 

 1905. Metnbrampora abortive Johns., Proc. Acad. Nat. Sci. 

 Phil. 1905, p. 5. 



Description. Zoarium consisting of cyhndrical branches about 

 .5 mm. in diameter, which sometimes bifurcate, and which rise 

 from a more or less irregular incrusting base. Zooecia arranged 

 in. from six to^ eight vertical columns upon 4:he cylindrical 

 branches, usually opposite in adjacent rows sO' as^ toi form annu- 

 lar rows also ; upon the expanded base the zocecia are irregularly 

 arranged. Each zooecium about .25 mm. in length, usually di- 

 vided into two portions, the aperture below, elliptical in outline, 

 surrounded by a raised border, about .15 mm. in length at the 

 summit of the border ; above the aperture is a smaller, depressed, 

 quadrangular or sub-crescentic area also surrounded by a raised 

 border, in some zooecia, perhaps in all when they are perfect,, 

 this region is covered by a domeshaped wall to- form an ovicell. 

 Avicularia small, equaling the zooecia in number, and placed in 

 the angles between them, surrounded by a raised border. Upon, 

 the expanded basal portion of the zoarium the zooecia are irregu- 

 larly arranged, with the apertures more oval in outline, with the 

 avicularia less numerous and irregularly arranged. 



Remarks. — The basal expansions of this species were originally 

 described as a distinct species under the name Membranipora 

 abortiva G. & H., but the two supposed forms are evidently but 

 different parts of the colonies of a single species. 



Formation and locality. — Vincentown limesand, Vincentown 

 (154). Timber Creek and near MulHca Hill (Gabb and Horn). 



Geographic distribution. — New Jergey. 



Genus OnychoceIvIvA JuUien. 



Onychocella digitata (Morton). 



Plate XXIIL, Pigs. 7-10. 



1834. Bschara digitata Mort., Synop. Org. Rem. Cret. Gr.. U> 



S., p. 79, pi. 13, fig. 8. 

 1845. Bschara digitata Eons., Quart. Jour. Geol. Soc. Eond.,. 



vol. I, p. 73, fiigs. c, d, g, ( ?a, b), (not e, f). 



