Tol. 50.] BRYOZOA FROM THE MIDDLE LIAS. 83 



Traces of an erect, hyaline, globose ovicell are present rarely on 

 the wall of the zooecium above. (PI. VII. fig. 0.) 



Cistern-cell about thrice the length and breadth of the common 

 zocecia, occupying their place in the zoarium, vertical, ending in a 

 broad, spout-like process, without recess or lower opening. (PI. VII. 

 fig. 7.) Surface covered with the protruding ends of surface-pores 

 like the zoarium. 



[Further study has enabled mo to discover a primary plate, 

 pierced with one opening of varying shape, or with several segments. 

 It is deep-seated, and the termination or sub-termination of the 

 zocecial tube is closed with the apertural plate. Presumably from 

 the primary plate arises the central tubule, on the upper side of 

 which are the various tubes and septal divisions making up and 

 leading to the inner part of the ovicell (one sees the outer or supra- 

 oral part of the ovicell traced on the zocecial wall). Below the 

 central tubule is what I take to be the true zooecial tube which 

 opens within the mouth. Apparently it turns outwards with the 

 closing up of the mouth by the mouth-plate with the infundibu- 

 liform opening, and merges into and becomes a labial aperture. A 

 scutum (or lip-pore) is traced on the under lip, but it and the con- 

 nected part of the apertural plate are generally broken away ; see 

 PI. VII. figs. 13, 14. The spherical bodies borne on the tubule of 

 forma quarta appear to be reproductive. I have been greatly aided 

 by the study of specimens such as Liripora, of P. H. MacGillivray, 

 kindly given to me by Miss E. C. Jelly, whom few surpass in 

 knowledge of bryozoa. The study of the Australian forms 

 which Mr. P. H. MacGillivray has worked out so well is a clue 

 to the study of the Jurassic types, for the bryozoan fauna, like the 

 general Jurassic fauna, finds kindred forms in Australian seas. — 

 January 24th, 1894.] 



In a Diastoporidian form from the Inferior Oolite (Pea Grit) of 

 Selsey Hill, given to me by Mr. Charles Upton, of Stonehouse, I 

 have noticed similar giant or cistern-cells. 



The beautifully-preserved terminations of the surface-pores are 

 shown in PI. VII. fig. 15. 



In many instances the zocecia figured are from one zoarium. 



EXPLANATION OF PLATES V.-VII. 



' Plate V. 



Fig. 1. Cistcrnifcra inconstans, gen. & sp. iioy. Zooecium with infundibuliforin 



opening, aperture, and labial pore. X 60. 

 2. „ ,, Zooecium with avicularian cell and broken 



apertural plate. X 60. 

 3,6. „ „ Zocecia with tracery of supra-oral ovicell. x60. 



4,5,8. „ „ Zocecia. x60. 



7. ,, „ Top of zooecium, showing the central tubule. 



XGO. 

 9. „ „ forma prima. Zooecium with apertural plate 



and aperture. X60. 

 10,11. „ „ „ Oistem-cella. X60. 



12. ,, ,, ,, Zooecium with tubule. X60. 



13. ,, ,, „ with apertural plate. X60. 



g2 



