No. 1797. 



NEW TUBVLIPOROID BBY0Z0A—BAS8LEB. 



523 



to being practically unconstricted, as in Stomatopora, tends also to be 

 exsert, as in that genus. The proximal constriction of the zooecium, 

 although shght, allies the species to Corynotrijim, but the remaining 

 characters are the same as in Stomatopora. The two remaining 

 species of the section, C. scliuclierti and C. canadensis, are more nearly- 

 related to Corynotrypa, since they have more constricted apertures 

 surrounded by a peristome. Their proximal constriction, however, 

 is much as in C. dissimilis, so that they must be considered as inter- 

 mediate forms. 



CORYNOTRYPA DISSIMILIS (Vine). 



Stomatopora dissimilis Vine, Quart. Journ. Geol. Soc. London, vol. 37, 1881, pp. 



615, 616, figs. 1-8; vol. 38, 1882, p. 50.— Bassler, Bull. U. S. Geol. Surv., 



no. 292, 1906, p. 15, pi. 4, figs. 15-19. 

 Stomatopora recta Ringueberg, Bull. Buffalo Soc. Nat Hist., vol. 5, 1886, p. 20, 



pi. 2, figs. 15, 15a. - ! 



Stomatopora minor B.E-SNIG, Arkivfiir Zool., Kong. Sven. Vet.-Akad. Stockholm, 



vol. 3, no. 10, 1906, p. 24, pi. 3, fig. 6. 

 Aulopora, species. Hall, Nat. Hist. New York, Pal., vol. 2, 1852, pi. 50, figs. 



27, 29. 



Original description. — "Zoarium adnate, branching, generally 

 attached to stems of Crinoidea, very rarely to broken shells; branches 



Fig. 23.— Corynotrypa dissimilis. o and 6, a typical example of the species, X9 and X20, 



INCRUSTING THE EPITHECA OF THE BRYOZOAN DiPLOTRYPA NUMMIFORMIS. SILURIAN, ROCHESTER 

 SHALE, LOCKPORT, NEW YORK. C AND d, A POORLY PRESERVED SPECIMEN OF THE SPECIES, X9 

 AND X20, GROWING UPON A SPECIMEN OF HELIOLITES. EARLY SILURIAN, LyCKHOLM FORMA- 

 TION, Kertel, Island of Dago, Baltic Sea. 



linear, sometimes wavy and anastomosing. Zooecia invariably uni- 

 serial, and, in the best preserved, very finely ribbed transversely; 

 the oral extremity slightly raised; orifice circular or subcircular. 

 Ooecial cells rather ventricose and strongly ribbed ( ?). Each normal 

 zooecium about half a fine; average about 6 to 3^ lines." 



