18 MR. A. W. WATERS ON THE MARINE 



In figure 10 the zooecia from various parts of the colony are placed 

 together to show the characters. 



Loc. Florida, 13-35 fath. (Smitt) ; Bermuda ( Verrill) ; Ceylon (Thornely) ; 

 West Indies and Malacca (Levinsen) ; on a coral from S. Africa in the Jelly 

 Collection in the Victoria University Museum ; Capo Verde Islands (St. 

 Vincent Harbour, 10 fath.), collected by Crossland. 



PSchizoporella OLIGOPUS, Robertson. (Plate 2. figs. 5, 6.) 



Schizuporella oligopus, Robertson, " The Incrusting- Chilostomatous Bryozoa of the West 

 Coast of North America," Univ. of California, Pub. in Zool. vol. iv. (1908) p. 292, pi. 20. 

 figs. 50, 51, 52. 



The radicles occur to nearly all the zooecia, and are seen at the growing 

 edge, even when no polypides have been formed, the number is most 

 frequently 6-8 but there may be 10, and a few zooecia have none. Similar 

 chitinous radicle-tubes occur in many Cheilostomata — for instance, in Mem- 

 branipora patellaria (Moll), Waters *, which is often thus attached to large 

 Melobesia, and the specimen of S. oligopus from the C. Verde Is. is also on 

 Melobesia. These radicles are at first a tubular projection at the end of 

 which is a chitinous tube attached to the Melobesia. 



At the junction of the zooecia there is a space, as mentioned by Dr. Alice 

 Robertson. My specimens of S. argentea, Hincks, from Tahiti, which are 

 co-types, do not show the spaces at the junction of the zooecia, nor do those 

 from the Red Sea, which have a calcareous opaque area in the middle of the 

 dorsal surface, as described by Hincks, and there is considerable irregularity 

 in the number of radicles. 



The anterior surface of the zooecia does not usually show pores round the 

 border, but, when examined from the interior, a row at the border is seen 

 between the granula and over the surface generally, but none are visible 

 until Eau de Javelle has been used. 



Tbe position of the avicularium close up to the oral aperture on one side 

 and the thin operculum led to my calling it Rhamplwstomella before 

 recognizing that it had been described. It will be noticed that while the 

 umbo is central, when there is no avicularium, yet when an avicularium 

 ©ccurs the umbo is on the other side. The aperture of the ovicelligerous 

 zooecia are much wider than those of the other zooecia' and are differently 

 shaped, as the sinus is less marked. This is not alluded to by Dr. Alice 

 Robertson, but the figures indicate a difference. No difference is noticeable 

 between the zooecial and ovicelligerous apertures of S. argentea. No spines 

 have been seen. There are about 16 tentacles. It must remain an open 

 question whether the difference (if any) in the frontal pores justifies a variety 

 or new species. 



* Waters, " Bry. of the Bay of Naples," Ann. Mag. Nat. Hist. ser. 5, vol, iii. (1879) 

 p. 120, pi. 10. figs. 8, 9. 



