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ocecia have hitherto not been made out with certainty, neither in fossil nor in 

 recent species of this genus; but the reference of the above mentioned species to 

 the genus Onychocella does not seem to me to be unquestionable. The presence 

 of avicularia with wing-shaped lateral expansions is not conclusive. I have found 

 quite similar avicularia in a tropical Microporella species. With regard to the 

 zooecia themselves they seem to be more like those found in Callopora Flemingi 

 and cognate species, as there seems to be a distinction between a strongly de- 

 pressed cryptocyst surrounded by a projecting margin and an arched, proximal 

 gymnocyst. The rather large ocecium issues from the latter and is in size, form 

 and position unlike the ooecia, which I have found in a series of recent and 

 fossil species of the genus, and which are very little conspicuous, so little in fact, 

 that they have hitherto been overlooked. 



While all the other zooecia have a sharp and deep sutural furrow in the 

 whole of their periphery, which forms the boundary between the projecting mar- 

 gins of their own and those of the surrounding zooecia, such a sutural furrow is 

 wanting in the distal end of the ooecium-bearing zooecia, and the proximal end 

 of the distal zooecium does not as in the other zooecia end in a low, rounded, 

 projecting margin, but in a somewhat higher, more or less distinctly prominent 

 swelling (the frontal wall of the ocecium) which is but indistinctly marked off 

 from the zooecium, and which seems to be covered by its frontal membrane. 

 This slightly prominent, rounded pent-roof is on either side separated from the 

 marginal cryptocyst of the proximal zooecium by a sutural furrow. In the interior 

 the frontally ascending distal wall touches the distal end of this swelling, and 

 between the zooecial operculum and the margin of the ocecium we find a slightly 

 chitinized ooecial operculum. Reference may be made to the schematic figure 

 (PI. XXIV, fig. 10.), the dotted lines in which show how I picture the inner 

 parts of this ocecium. 



Cupularia Lamouroux. 



The zooecia broadly rhombic, without frontal gymnocyst, but with a depressed 

 cryptocyst perforated by a larger or smaller aperture. No spines. Each distal wall 

 with one, and the distal half of each lateral wall with several (up to 6), scatte- 

 red, uniporous rosette-plates. The lateral walls are common to the contiguous 

 neighbouring zooecia. On the distal side of each zooecium we find an asymme- 

 trical, independent vibracalum with a long flagellum and an angularly bent, kid- 

 ney- or bean-shaped opening. No ooecia. The species hitherto described occur in 

 free, discoidal colonies with a thick basal surface covered by a membrane, the 

 radiating furrows of which correspond with radiately arranged zooecial rows. 



