CYCLOSTOMATOUS BRYOZOA CaNU AND BASSLER 



73 



Sainte-Croix, Swit- 



Occurrence. — Lower Cretaceous (Valangian) 

 zerland (common.) 



CotyjMS.— Cat. No. 69925, U.S.N.M. 



DIPLOCAVA INORDINATA, new species 



Plate 11, figs. 1-5 



Description. — The zoarium is free, cylindrical, arborescent; the 

 base is enlarged and placed on a substratum. The large tubes 

 appear very irregularly among the others, sometimes isolated, some- 

 times grouped. The facettes are hexagonal, little visible, smooth, 

 very little convex, perforated at the middle by the aperture. The 

 aperture is orbicular, large or small, according to the nature of the 

 tubes, surrounded by a peristome which is scarcely salient and very 

 thin. The orifices of the tubes without 

 facettes are polygonal. 



Measurements. — Inner orifice of small 

 tubes, 0.16 mm.; diameter exterior orifice 

 of small tubes, 0.20 mm.; diameter inner 

 orifice of large tubes, 0.20-0.24 mm.; diam- 

 eter exterior orifice of large tubes, 0.30 

 mm.; diameter aperture, small tubes with 

 facettes, 0.10 mm.; diameter aperture, large 

 tubes with facettes, 0.14 mm.; diameter of 

 the large branches, 3 mm. 



Variations. — As our specimens are numer- 

 ous, we have been able to study the varia- 



, • TXT 1 -i 1 • 1 r J. Figs. 37. — Diplocava inordinata, new 



tions. We have observed zoarial fragments ^^^^^^^ Longitudinal section, 

 formed uniquely of large (fig. 3) or small 

 (fig. 2) zooecia, fragments with both kinds 

 of zooecia (fig. 4), and finally a fragment 

 with tubes bearing facettes (fig. 5) . 



In longitudinal sections the tubes have a diameter quite variable 

 in their recurved expanded parts. 



Occurrence. — Lower Cretaceous (Valangian): Sainte-Croix (Vaud), 

 Switzerland (common) . 



Coty pes. ^Csit. No. 69926, U.S.N.M. 



DIPLOCAVA ORBICULIFERA, new species 



Plate 11, figs. 6-8 



Description. — The zoarium is free, cylindrical, ramose. The large 

 tubes are grouped in very regular orhicular areas irregularly arranged 

 on the zoarium. The small tubes are much more numerous, hexag- 

 onal, arranged in quincunx. 



Measurements. — Diameter orifice of small tubes, 0.10 mm.; diam- 

 eter of large tubes, 0.20 mm. ; diameter of zoarium, 10 mm. 



X 16, exhibiting the variations in 

 diameter of the tubes at their 

 extremity. Lower Cretaceous 

 (Valangian): Sainte-Croix, 

 Switzerland 



