Vol. 50.] THE INFERIOR OOLITE OF SHIPTON GORGE. 77 



Zoarium erect, cylindrical, of nearly equal thickness throughout. 

 Zooecia tubular, obacurely arranged in a linear series, often com- 

 pressed, exsert for one half or more of their length (PI. III. fig. 27). 



Zooecia : (1) PI. III. fig. 33, upper lip arched, aperture coarctate, 

 peristomial aperture ovately triangular, thick ; ovicell supra-oral, 

 front mural pore triangular : (2) PI. III. fig. 30, compressed, mouth 

 filled with tubules, front wall having a furrow and a narrow ovoid 

 opening ; at the base an oval opening with very fine tubules 

 (? ovicell) : (3) PL III. figs. 25, 26, compressed, with two terminal 

 rostra — one with tubules, the other with a narrow opening, a small 

 opening at the junction of the rostra, an ovicell-sac or opening at 

 the base, as in Lekgtliopora Jiystrix, MacGil. 



Zooecial covers (PI. III. fig. 29) are scattered on the zoarial 

 surface, whether pushed off at a certain stage of development, or 

 sheared off in fossilization, it is hard to say. Surface punctate, with 

 fine inter-pores. 



The twin rostral processes spring from above a central opening 

 or aperture, and are similar to the twin rostral processes of Cellepora 

 hastigera, Busk. 1 



Summary/. 



1. The discovery in the Inferior Oolite of the South of England 

 of bryozoa belonging to the Cheilostomata, a sub-order not definitely 

 known below the Cretaceous group. 



2. The occurrence in the same colony of bryozoa having the form 

 of ovicell and long tubular zooecia of the Cyclostomata, together with 

 the appendages and apertures of the Cheilostomata. 



3. The description of a new genus Pergensia, characterized by a 

 long cylindrical axis, globose ovicell- sacs on the body of the 

 zoarium and supra- oral ovicell, zooecia with trifoliate opercular 

 aperture or with various openings and tubules. 



4. The description of the following species : — 



Pergensia nidulata, P. major, P. minima, P. porifera, P. ampho- 

 ralis, P. jugata, P. jugata var. bi-gibbosa, and P. galeata. 



EXPLANATION OP PLATES II.-IV. 

 Plate II. 

 Fig. 1. Pergensia nidulata, sp. nov. xl2. 



2. ,, ,, Longitudinal section, showing the axial tube. Xl2. 



3. „ major, sp. nov. Longitudinal section, showing the axial tube 



and ovicell-sac with termination. X 12. 



4. „ „ Xl2. 



5. „ amphoralis, sp. nov., var. a. X25. 

 (5. „ porifera, sp. nov. x25. 



7. „ sp. Longitudinal section. X20. 



8. „ amphoralis, sp. nov. X 12. 



9. „ jugata, sp. nov. X 12. 



10. „ „ Longitudinal section, showing the axial tube and diver- 



gent growth of zooecia. X 12. 



11. ,, „ var. bi-gibbosa. xl2. 



12. ,, minima, sp. nov. X 12. 



1 By Mr. R. Kirkpatrick's courtesy I was enabled to examine Busk's types 

 in the British Museum (Natural History), at South Kensington. 



