ilAKYLAM) GEOLOGICAL SURVEY 429 



adopted type of the genus, but we believe it is sufficiently distinguished 

 by the punctate instead of smooth walls of its zooecia to deserve another 

 name. 



Occurrence. — St. Mary's Fokmatiox. St. Mary's Eiver. Chop- 

 TAXK Formation. Greensboro. Calvert Formation. Plum Point, 

 Chesapeake Beach. 



Collections. — Maryland Geological Survey, U. S. National Museum. 



Cellepora cribrosa n. sp. 

 Plate CXVII, Figs. 5, G. 



Description. — Zoarium forming small irregular compressed masses. 

 Zooecia very irregularly disposed, some erect, others prostrate, 0.5 mm. 

 to 0.7 mm. long, by 0.4 mm. to 0.6 mm. wide; surface strongly punc- 

 tate; orifice rounded, the normal form showing a slight constriction a 

 little below the middle, where a small tooth projects into the cavity from 

 each side; peristome thick and more or less elevated, ring-like. Avicu- 

 laria of moderate size, more or less acuminate ovate, attached to and 

 projecting beyond the plane of the inferior side of the peristome; rarely 

 absent. Ovicells few, known only in the broken condition in which 

 they appear as deep semicircular excavations in front of the zooecial 

 orifices. 



Though doubtless new as an American fossil, we are not bv any means 

 satisfied that this form has not been before described. It is like many 

 other species now referred to Cellepora, but so far as we could learn not 

 identical with any. 



In its^ general aspect there is much to remind of our Schizoporella 

 cumulata, but when carefully compared the zooecial orifices and avicu- 

 laria prove to be quite different. 



Occurrence. — Calvert Formation. Eeed's. 



Collection. — Marvland Geological Survey. 



