MOLLUSCOIDEA. 351 



Description. Zoarium consisting of quadrangular branches, 

 which are rounded at the angles. Zocecia arranged on the four 

 faces, the apertures alternating in position, the proximal margin 

 of the aperture produced into a prominent lip, which is pointed 

 and projects forward in the center, emarginate on the sides, the 

 distal margin of the aperture merging into the surface of the 

 zoarium. 



Remarks. No specimens agreeing with the original figure and 

 description- of this species have been met with in the recent collec- 

 tions. Certain specimens do occur, however, which have a large 

 number of accessory pores, absent in Gabb and Horn's figure, 

 which are believed to belong here. The type is apparently lost, 

 but it was probably a specimen in which these pores were wanting. 



Formation and locality. Vincentown limesand, Timber Creek 

 (Gabb and Horn). 



Geographic distribution. New Jersey. 



Porina coronata (Reuss)? 



Plate XXVI., Fig. n. 

 1869. Acropora coronata Reuss, Pal. Stud., p. 277. 



Description. Zoarium consisting of flattened branches from 

 i mm. to 4 mm. in width, and I mm. or less in thickness. Zocecia 

 not sharply differentiated externally; arranged more or less 

 irregularly over the entire surface, sometimes in quite regular 

 longitudinal lines, zocecial apertures circular, about 0.16 mm. in 

 diameter, the interspaces covered with numerous, more or less 

 irregularly scattered accessory pores. 



Remarks. This species seems to "be identical with the 

 European form, but until authentic specimens can be actually 

 compared, the identification may be made with a query. 



Formation and locality.. Vincentown limesand, Vincentown 



(154). 



Geographic distribution. New Jersey. 



