i iS 



The inflated part of the ovicell (which has been figured by Waters, 1889) commences 

 verv suddenly on its proximal side, and it is hardly possible to distinguish which zooecium has 

 given rise to it. There is, however, every probability that, as in other Cyclostomes, the ovicell 

 is at first a zooecium, the distal end of which becomes greatly enlarged and dilated as the 

 result of the development of an egg into an embryo which gives rise to numerous larvae by 

 a process of embryonic fission. In fig. 6 only a single ovicell is present; and it is thus easy 

 to distinguish its lateral outlines. The ooeciostome is in this case a short tube which rises 

 symmetrically from the middle of the distal border of the ovicell, terminating in a nearly circular 

 ooeciopore which looks frontally. 



In fig. 7 the ovicells form a ring which is quite complete except at one side, where 

 the growth of the colony has no doubt been checked by some object on which it was growing. 

 Four ooeciostomes can be distinguished, each of which lies near the proximal end of a pluriserial 

 group of connate zooecia, representing the peripheral end of one of the series of zooecia which 

 started near the centre of the colony. As these peripheral groups (about 26) are more numerous 

 than the radial ridges (about 1 6) in the more central part of the colony, it may be concluded 

 that some of the series have bifurcated, but that the point of bifurcation is concealed by the 

 ovicell. The number of ooeciostomes present indicates that there are probably four ovicells in 

 specimen 424. A.; but the lateral union of the ovicells is so intimate that their limits cannot 

 be made out. It is not impossible that they have fused with one another laterally, so that the 

 cavities have become confluent; but it cannot be ascertained whether this is the case or not 

 without destroying the specimen. 



424. A. was growing on a small Gasteropod shell, and the Japanese specimen was also 

 on a shell. 104. C. is on the basal surface of a Retepore (104. B.), two or three of the fenestrae 

 of which are obliterated by its marginal lamina. 



M e a s u r e m e n t s , in u : — 



Greatest diameter of colony, fig. 7, 4,400; 

 Greatest diameter of ovicell-ring, fig. 7, 3,300; 

 Radial diameter of the same ovicells, 600 — 700 ; 

 Width of ovicell, fig. 6, 850 ; 

 Diameter of ooeciopore, 80 ; 

 Diameter of orifices, 100. 



Tubuliporidae Johnston. 



Tubuliporidae (pars), Johnston, 1838, "Hist. Brit. Zooph.", Ed. 1, p. 267. 

 Tubuliporidae (pars), Johnston, 1847, Ibid., Ed. 2, p. 265. 

 Tubuliporidae (pars), Hincks, 1880, "Hist. Brit. Mar. Pol.", p. 424. 

 Tubuliporidae and Idmoneidae auctt. 



The Family Tubuliporidae, as used by Johnston in 1838, included the two genera 

 Tubulipora and Di$copora\ the former comprising species of Berenicea (Diastofiora) as well as 



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