AKT. 21 CYCLOSTOMATOUS BRYOZOA CANU AND BASSLER 7 



From our study of the Sainte-Croix specimens we have observed: 



(1) The variety alectodes Gregory, 1899 (p. 38), known hitherto 

 only from the Upper Cretaceous, is now recognized in the Lower 

 Cretaceous by specimens indicating it is only one of the zoarial 

 forms. 



(2) A specimen was noted expanded almost into the Berenicea 

 growth form, as in the variety elevata Gregory, 1899, from the 

 Lower Cretaceous. 



(3) Another specimen corresponds rigorously to the figure pub- 

 hshed by D'Orbigny. 



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

 Switzerland, Censeau (Doubs), Villers-le-lac (Jura), and Berkhngen 

 (Germaine) , France. 



Plesiotype.—Csit. No. 69834, U.S.N.M. 



PROBOSCINA RADIOLITORUM D'Orbigny, 1851 



Plate 27, figs. 1, 2 



1899. Proboscina radiolitorum Gregory, Catalogue of the Cretaceous Bryozoa in 

 the British Museum, vol. 1, p. 48, pi. 3, fig. 5. (Bibliography, geolog- 

 ical distribution.) 



The figured specimen is incrusting a sponge. Although this species 

 is easy to determine, it has not hitherto been observed in the Lower 

 Cretaceous. 



Occurrence. — Lower Cretaceous (Aptian) : Faringdon, England. 



Pledotype.—C&X. No. 69835, U.S.N.M. 



PROBOSCINA ZIC-ZAC D'Orbigny, 1853 



Plate 29, fig. 7 



1853. Proboscina zic-zac D'Orbigny, Pal6ontologie frangaise, Terrain Cr6tac6, vol. 

 5, p. 847. pi. 631, figs. 6, 7. 



Measurements. — Diameter of orifice, 0.08 mm.; diameter of peri- 

 stome, 0.16 mm.; length of zooecium, 0.32-0.40 mm. It seems to us 

 that Gregory is in error in identifying this species with Proboscina 

 fasciculata Reuss. The micrometric dimensions are different. 



Occurrence. — Lower Cretaceous (Aptian) : Faringdon, England. 



Geological distribution. — Lower Cretaceous (Neocomian) : Vassy 

 (Haute Marne), France, and Sainte-Croix (Vaud), Switzerland 

 (D'Orbigny). 



Plesiotype.— Cat. No. 69840, U.S.N.M. 



PROBOSCINA RICORDEAUANA D'Orbigny, 1853 



Plate 27, figs. 7, 8 



1853. Proboscina ricordeauana D'Orbigny, Pal^ontologie fran^aise, Terrain Cr^- 

 tac6, vol. 5, p. 850, pi. 750, fig. 6. 



The specimen which we illustrate seems to agree very well with 

 the one figured by D'Orbigny. It incrusts a sponge. 



