NO. 6 BRYOZOAN GENUS TREMATOPORA — BOARDMAN 7 



Leioclema asperum (Hall) 1852, Rochester shale, Lockport, N. Y. (Only 

 Bassler's plesiotypes of 1906 available.) 

 L. confertiporum (Hall) 1883, Hamilton group, New York. 

 L. decipiens (Hall) 1883, Hamilton group, New York. 

 L. passitabulatum Duncan 1939, Traverse group, Michigan. 



The region now considered to be the inner region of the exozone in 

 species of Leioclema from the Hamilton group of New York was 

 interpreted as the outer part of the endozone (Boardman, in press) 

 and diaphragm pores were overlooked. 



TREMATOPORA TUBERCULOSA Hall 



PI. 1, figs. 1-4; pi. 2, figs. 1-3 



1852. Trematopora tuberculosa Hall, Paleontology of New York, vol. 2, p. 149, 



pi. 40A, figs. ia-g. 

 1883. Trematopora tuberculosa Hall, Ulrich, Journ. Cincinnati Soc. Nat. Hist., 



vol. 6, p. 259, pi. 13, figs. 2, 2a, 2b. 

 1906. Trematopora tuberculosa Hall, Bassler, U. S. Geol. Surv. Bull. No. 292, 



P- 43, PL 13, figs- 15, 16; pi. 17, figs. 1-3; pi. 25, fig. 8. 



TYPE DATA 



Lectotype (Hall, 1852, pi. 40A, fig. ia) and the two paratype zoaria 

 from syntype suite No. 1747, American Museum of Natural History. 



MATERIAL STUDIED 



In addition to the primary types, 55 fragmentary topotype zoaria 

 were studied. The topotypes are from U. S. National Museum col- 

 lection No. 2998 and cat. No. 43618 collected by E. O. Ulrich. U. S. 

 National Museum catalogue numbers of illustrated topotypes are 

 137847 to 137850. 



OCCURRENCE 



Rochester shale member of the Clinton formation, Lockport, N. Y. 



DESCRIPTION 



Zoaria. — Zoaria are ramose and branches are circular to elliptical 

 in cross section. Branch arrangement was affected by branches rising 

 from conspecific secondary growth superimposed on the normal bi- 

 furcating pattern. Branches of secondary growth produced irregu- 

 larities in branch arrangement, commonly causing branches to 

 anastomose and form erratic and confused zooecial growth at surfaces 

 of contact. These irregularities in branch arrangement were formed 



