American Palceozoic Bryozoa. 



169 



This neat species is mentioned in this connection, only because it 

 shows a variation in one character from the typical species of the 

 genus. Nameh', the branches of this species do not retain a certain 

 width throughout (as is very nearly the case in the more typical 

 species), but vary, from below upwards, between the extremes of one 

 tenth and three tenths of an inch. The rows of cells are increased by 

 interpolation. In all other respects, S. gilberti has the characters of 

 the genus as above specified. 



Stictopora basalis, n. sp. (PI. VIII., figs. 4 and 4a.) 

 Zoarium branching at intervals of about .2 inch, and attached to 

 foreign bodies below by a broad, striated, and non-poriferous basal ex- 

 pansion. Branches from .08 inch to .12 inch in width ; thickness of 

 same, not exceeding .03 inch. Non-poriferous margin rather wide, 

 smooth. Cells small, with thick walls and elliptical apertures ; ar- 

 ranged in from ten to twelve alternating longitudinal series, between 

 more or less elevated lines. Measured longitudinally, eight cells occiipj 7 " 

 the space of .1 inch; transversely, there are twelve rows of cells in the 

 same space. 



The small cells, and the profuse branching of the zoarium, are the 

 distinguishing features of the species. 



Formation and locality: Trenton group. Collected by Prof. J. M. 

 Safford, at Shelbyville, Tenn. 



Stictoporella interstincta, nov. gen. et sp. (Plate VIII., figs. 9, 9a.) 

 Stictoporella, gen. char, ante, p. 152. 



Zoarium small, branching several times at intervals of from .1 inch 

 to .3 inch. Branches thin, with a width usualfv a little less than .1 

 inch. Cells comparatively large, with elliptical apertures, and rather 

 thin walls; arranged in somewhat irregular, alternating, longitudinal 

 series, without airv raised lines between them. Measured diagonally, 

 eight cells occupy the space of .1 inch; in the same space longitudin- 

 ally there are six cells. Between the ends of the cell-apertures there 

 are always two, sometimes three or four, elongated interstitial pits, and 

 along the edges of the branches there are from one to three obliquely 

 directed series of similar pits. 



This species is closely allied to Stictoporella Jlexuosa ( Ptilodictya 

 Jlexuosa, James), from which it differs in having wider, and oftener 

 divided branches, and less regularly distributed cells. Besides the 

 type species and 8. Jlexuosa, James, the genus will probably embrace 

 Ptilodictya excellens, Billings, from the Anticosti group, of Canada. 



Formation and locality : At river quarries, opposite the city of 

 Cincinnati, Ohio. 



