ART. 22. CYCLOSTOMATOUS BRYOZOA CANU AND BASSLEK. 57 



no basal lamella ; it bears on the dorsal a wall formed of short nem- 

 atopores with very thick walls. 



Genotype. — Osculi'pora {Eetepora) truncata Goldfuss, 1827 (pi. 

 23, figs. 1-6). 

 Range. — Cretaceous (Campanian-Danian.) 



The known species belonging to this genus in addition to the geno- 

 type are: 



Osculipora repens Hagenow, 1851. Maastrichtian, Danian. 

 OscuUpora houzeaui Pergens, 1894. Maastrichtian. 

 Osculipora royana D'Orbigny, 1850. Maastrichtian, Cam- 

 panian. 

 Afinities. — The place of the ovicell is not constant; it may b& 

 lateral, frontal, or dorsal ; but the nature of the tubes is always the 

 same. Exteriorly this genus very much resembles Diplodesniopora; 

 it differs from it in its cylindrical and nonwidened tubes. It differs 

 from Desmepora Lonsdale, 1850, in the absence of adventitious pores 

 on the frontal and in its cylindrical tubes. 



OSCULIPORA EEPENS Hagenow, 1851. 



Plate 23, fig. 7. 



1851. Truncatula repens Hagenow, Die Bryozoeu der Maastrichter Kreitle- 



bildng, p. 36, pi. 3, fig. 1. 

 1909. Osculipora repens Gregory, Catalogue Fossil Bryozoa in British 



Museum, Cretaceous, p. 61, figs. 22, 23 (Bibliography). 



Stmcture. — We have not enough specimens of the genotype to make 

 sections, but there is no doubt of the generic identity of the present 

 species with the genotype. However the ovicell is placed here on 

 the frontal between the fascicles ; it is less globular than in the other 

 species. 



In transverse section tlie tubes are almost of the same size; they 

 are therefore cylindrical ; the walls of the exterior tubes are thick. 

 The dorsal wall of the zoarium is very thick and perforated by small 

 pores corresponding to the nematopores. When the transverse sec- 

 tion is made at the level of the fascicles, these appear cylindrical. 



In longitudinal section the tubes are cylindrical, fasciculated with 

 adjacent peristomes; they are separated by a small interzooecial 

 canal. They bifurcate at all heights and in the vicinity of the dor- 

 sal. The tubes of the same fascicle grow successively by dorsal gem- 

 mation. Th6 nematopores are short; their walls are very thick in 

 the branches, but they are much less so at their extremity. 



The posterior face (dorsal) is smooth and covered by a very thin 

 epitheca ; this disappears at the least wear and the nematopores ap- 

 pear; they are directed from below upward according to the rule 

 of their formation. Gregory 1909 has made the same observation in 

 Osculipora truncata Goldfuss, 1827. 



