NORTH AMERICAN EARLY TERTIARY BRYOZOA. 215 



Affinities. This species differs from Velumella plwata in its wrinkled poly- 

 pidian convexity, in its non transverse opesium, and its linear opesiules. We have 

 observed a normal zooecium replaced by a perforated calcified zooecium. 



Occurrence. -Upper Jacksonian (Ocala limestone) : along Chipola River, east 

 of Marianna, Florida (very rare). 



Holotypc.Crt. No. G3975, U.S.N.M. 



Genus DIPLOPHOLEOS Canu and Bassler, 1917. 



1917. DiplophoJeos CANU and BASSLER, Synopsis of American Early Tertiary Clieilostome 

 Bryozoa, Bulletin 96, United States National Museum, p. 2G. 



The retractor muscles of the polypide are attached in the median axis of the 

 zooecium. The lateral indentations are symmetrical and almost transformed into 

 true opesiules. The onychocellaria are straight, their opesium is oval, with a 

 denticulated poster; the mandible is bimembranous. The mural rim is not sep- 

 arated from the cryptocyst. The zooecium is closed by an operculum attached to 

 the ectocyst. The axis of rotation of the operculum is indicated by two opesial 

 denticles. The zooecial opesia are dimorphous; one kind is elongated and the other 

 transverse. 



Genotype. Diplopholeos fusiforme Canu and Bassler, 1917. 



Range. Jacksonian, Vicksburgian. 



This genus differs from Rectonychocclla in its dimorphous opesia and its poly- 

 pidian convexity, which is constant, protruding, and accompanied by two nearly 

 complete opesiules. We are ignorant of the reason for the opesial dimorphism 

 often accompanying zooecial dimorphism. 



DIPLOPHOLEOS FUSIFORME Canu and Bassler, 1917. 



Plate 34. figs. 11-14. 



1917. DipJnpJioJeos fusiforme CANU and BASSLER. Synopsis of American Early Tertiary 

 Cheilostome Bryozoa, Bulletin 96, United States National Museum, p. 26, pi. 3, fig. 2. 



The zoarium incrusts shells and pebbles. The zooecia are hexagonal, a little 

 elongated, separated by a narrow furrow or united among themselves by their mural 

 rims; the cryptocyst is deep, concave, shorter than the opesium. finely granular; 

 the polypidian convexity is protruding, wrinkled or granulated, denticulated on 

 its opesial border; the lateral openings are deep, round, almost becoming true 

 opesiules; the opesium is elongated, semilunate, finely crenulated. The ovicell is 

 an inconspicuous distal convexity, sometimes limited by two lines of lateral sutjure. 

 The onychocellarium is narrow, fusiform, somewhat larger than the zooecia; the 

 opesium is median, oval, the point below, with a narrow and denticulated posterior; 

 the terminal point projects above the distal zooecium, but is very fragile; the distal 

 canal through alteration in fossilization fuses nearly always with the cryptocyst 

 of the distal zooecium. The heteromorphic zooecia are a little smaller; their 

 cryptocyst is longer than the opesium which then appears nearly transverse. The 

 ancestrula is of the same form as the zooecium. 



