JAMES TYPES OF BRrOZOA—BASSLEIi. 53 



species. The associated ptilodict3^oicls, with the exception of Sticto- 

 porella fiexuom., may be distinguished at sight by their jointed zoaria, 

 the articulation l)eing at the base alone as in Escharopora or at numer- 

 ous points as in Arthropora. The mesopores of S. flexuosa will 

 readily separate it from R. parallela. 



Occurreriee. — Lower beds of the Eden shale at Cincinnati, Ohio, and 

 vicinity. 



RHINOPORA VERRUCOSA Hall. 



Rhinopora verrucosa Hall, Nat. Hist. New York, Pal., II, 1852, p. 48, pi. xix, 



tig. l«-('. 

 Eschariria f distortu James, Paleontologist, No. 3, 1875, p. 21. 



The types of "Escharina / distorta show that this name is founded 

 upon specimens of the characteristic Clinton bryozoan Rhinopora ver- 

 rucosa. The specimens are embedded in solid limestone and show onl}^ 

 their epithecal side. In breaking the rock, the two leaves of the 

 l)ifoliate fronds of Rlunopora part along the smooth median plane 

 because the poriferous side of each leaf is rougher, and therefore 

 adheres to the rock. By means of thin sections, however, the iden- 

 tity of these fronds with ^///v^o/yrz/vc v'^/7'?ic'o».w, was proved beyond a 

 doubt. 



Occurrence. — The types of James's species were from the Clinton, 

 near Wilmington, Clinton County, Ohio. R. verrucom, is found gen- 

 erally in abundance at most localities in the New York and Ohio areas 

 of Clinton shale. 



SAGENELLA STRIATA James. 



Sagenella striata James, Paleontologist, No. 8, 1879, p. 22. 



The type specimens described under this name l)}^ Mr. James are 

 two small thin expansions parasitic upon bryozoa from the Eden 

 shale. The surface of these expansions is ornamented with long, fine 

 striae radiating from a similarly striated crater- like central area. A 

 careful examination of this surface with a lens, or, better still, of the 

 structure of the specimens by means of thin sections under the micro- 

 scope, shows that the stria? are the greatly elongated and generally 

 (confluent /official apertures of bryozoa with the wall structure charac- 

 teristic of the genus Excharopora. One can now infer from their gen- 

 eral shape and structure that the crater-like depressions of these 

 striated parasitic growths are the basaU sockets with which the pointed 

 end of the zoaria of Excharopora articulated. That this inference is 

 correct is proved by the occasional discovery of a zoarium with its 

 point in place in the basal socket or in such close proximit}' that their 

 relation to each other can not be doubted. It is also a fact that 

 wherever these attg,ched expansions occur, the erect fronds of one or 

 other of the species of Escharopora may always be found. 



By themselves these basal sockets show no specific differences, and 

 the species to which any particular specimen belongs must be deter- 



