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PROCEEDINGS OF THE NATIONAL MUSEUM 



Measurements. — Diameter of apertures, 0.10 mm.; maximum 

 zoarial width, 9 mm.; zoarial height, 14 mm. 



Structure. — The zoarial form is rather constant, ovoid or fusiform. 

 On the base, viewed from below, the tubes are arranged fan-shape 

 in the manner of Berenicea. 



Many of the zoaria appear to be formed of many lamellae inserted 

 one on the other. In reality thin sections show that this is not so 

 for there are no successive complete basal lamellae; sometimes the 



Fig. &.— Ceriopora ovoidea, uew species. B. Meridian section of another zoarium, X 16, in which the zonal 

 lines have been transformed into basal lamellae. The main zoarial tubes are oriented in a different 

 direction from those of the primitive zoarium. Lower Cretaceous (Valangiaa): Sainte-Croix, Switzer- 

 land 



zonal lines are transformed into basal lamellae but only along a part 

 of their course. This is an arrangement intermediate between that 

 of Ceriopora and of typical Reptomulticava, so that we do not know 

 into which genus this species as well as most of the following should 

 be placed. 



The • tubes are cylindrical, with concave diaphragms and with 

 peripheral gemmation. The walls are rather thick, moniliform in 

 a part of their course, and formed of two rows of vesicles in their 



