402 MR. A. W. WATERS ON THE RELATIONSHIPS 



six or eight zooecia surrounding the primary. The growth in the 

 surrounding zooecia in Cupularia is shown in my PI. 30. fig. 11, and Busk 

 has figured them in C. Johnsoni* , Busk; Selenaria metadata seems to have 

 six zooecia round the primary f. 



Canu mentions eight zooecia round the primary in Liundites Irevigata, 

 Oanu ; but some Lunulites as L. sella, Marsson and L. Goldfussi, Hag., have 

 only six. I have figured Selenaria concinna, Busk (PI. 30. fig. 9), showing 

 only five zooecia, but as there are three vibracular chambers these may be 

 taken as representing three zooecia. There are various Bryozoa in which the 

 primary is surrounded by eight zooecia, as Flustrella Mspida, Fab., from 

 Oban, and as shown by Barrois there are eight zooecia round the primary in 

 + Microporella impressa, And., and six in § Membranipora pilosa, L. In 

 M. lineata, L., there are also six, as is the case in M. nitida, Johnst., 

 M. Dumerilii, Aud., M. tenuirostris, Hincks, Miaropore'Ua diadema, MacG-., 

 M. ciliata, Pall., from Oban, and M. Malusii, Aud. These may be taken as 

 typical figures, even if there is some variation. In Cupularia, Selenaria, and 

 Lunulites, the younger zooecia, sometimes even to three rows round the 

 primary, have a calcareous perforated front, just as we have seen in the 

 ordinary zooecia of Cupularia Lowei, covered on the front by a membrane, to 

 which bundles of muscles passing through the frontal pores are attached to 

 draw it down, so that the structure of these is Microporidan, while the outer 

 zooecia have a Membraniporidan operculum. 



In some Selenariadse the opercular opening is more or less closed by 

 a tongue-like calcareous projection to which I have referred as occurring 

 in || Selenaria petaloides fossil from New Zealand, but in S. concinna 

 (PI. 30. fig. 9) it commences near the proximal end until at last the aperture 

 may be entirely closed. It seems that this closure must be compared with 

 those which I^[ have described over the operculum of Scliizoporella unicornis 

 and other Schizoporellidse, though it takes a rather different form. Maple- 

 stone ** has already referred to it. 



* Quart. Journ. Micr. Soc. vol. vii. pi. 23. fig-. 8. 



t I have made sections of the small (3-6 mm.) fossil Cellepora globularis, Rss. from the 

 Bartouian of S. Urbano di Mte. S. Greve, Vicentine, a species described by Eeuss bom Val 

 di Loute, but in his first description other species were included. Enclosed in the. colony, 

 but not in the middle, is a grain of sand without any small zooecia on it, so that there is no 

 reason for considering' that it grew upon the sand or for making' any comparison with 

 Selenariadse. There are two small oral avicularia in the peristomial tube, and this shows it 

 is either Cellepora or Lagenipora, but no ovicells have been seen. 



| Emb. des Bry, pi. 16. fig-. 2 (1877). § Loc. cit. pi. 15. fig. 9. 



|| Quart, Journ. Geol. Soc. vol. xxxix. p. 442, pi. 12. fig. 11 (1883). 



If Journ. Linn. Soc, Zool. vol. xxxiv. p. 15 (1918). 



** " Vict. foss. Seleuar.," vol. xvi. p. 217, pi. 25. fig. 8 (1904). 



