i 7 8 



Cincinnati Society of Natural Histo?y 



DIASTOPORINA FI.ABELLATA, n. Sp. 



tips 



Fig. h.—Diastoporina flabellata, n. sp. a, a complete zoarium of this species of the 

 natural size and magnified seven diameters, showing arrangement of zooecia, fine 

 interstitial stria? and obscure concentric wrinkles A small tubiculous annelid is 

 attached to the frond, b, portion of same xl8, to show the characters of the species 

 more clearly. 



Zoarium flabellate, small, bifoliate, very thin, 5.5 mm. wide. 

 Surface with obscure concentric wrinkles, and finely striated 

 parallel with the direction of the zooecia. Zooecia rather scatter- 

 ing, partly exposed, appearing as convex oval spaces with a small 

 oblique aperture, 0.05 mm. in diameter, at the distal extremity. 

 Small, non-celluliferous spaces occasionally. Under a high power 

 of magnification, the fine striae which cover the interpaces appear 

 as fine lines separating rows of exceedingly minute pores. 



This species is regarded as a Cyclostomatous bryozoan with 

 relations to Diastopora and Beroiicea. 



Position and locality : Rare at the top of the Trenton Shales, 

 near Cannon Falls, Minn. , where it is associated with Arthroclema 

 armatum, Helopora mucronata, Nematopora granosa and other 

 minute Bryozoa described in this paper. The horizon is a very 

 interesting one. 



