OVICELLS OE CYCLOSTOMATOUS BRYOZOA. 
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unique structure ; and, so far as I am aware, nothing of the kind 
has before been found. The base is narrow, hut the sac widens 
out, and then again becomes narrower ; the surface has a few 
large oval pores, and the ovicellular opening is a raised tube at 
one upper corner. The zooecial tubes spread out at the ends. 
It is placed, with hesitation, under I. Meneghini, as there are 
only four zooecia to a series ; but ITeller only figures four, and 
the number is not always constant in a colony. In a specimen 
from Naples, without an ovicell, of what I considered I. Mene- 
ghini, the zooecial tubes do not spread out at the end in the same 
way ; but sometimes a trace of this structure can be seen. The 
dorsal surface near tue ends of the branches is finely punc- 
tured, but near the base there are larger openings. I have 
only the one specimen with ovicells. 
IdmOjYEA irregularis, Meneghini. (PI. XIY. figs. 5 and 6.) 
This was found by the ‘ Challenger ’ off the Azores ; and Mr. 
Busk(p. 14) says, “ ooecial chamber? ” 
I have, however, previously (see Ann. Mag. Nat. Hist. ser. 5, 
vol. xx. p. 257, and Quart. Journ. Geol. Soc. vol. xl. p. 687) 
referred to the dorsal ovicell of I. irregularis-, but as it has 
never been figured, a normal ovicell is given (fig. 5) and a short 
abnormal one (fig. 6). 
The ovicellular aperture is wide, with a raised irregular funnel- 
shaped opening ; but in the young ovicells the upper part is flat, 
sloping inwards. One colony has eight ovicells, and five of 
these are intact, without showing any opening ; and from this 
we see how misleading this specimen alone would have been, 
as the young ovicells are without external orifices. 
A somewhat similar ovicell occurs on Filisparsa oraleeiensis, 
Stol. (Joe. cit. p. 687). 
Idmonea Milneana, d'Orh. (PI. XIV. fig. 8.) 
I have already referred to the ovicell of 1. Milneana (Ann. 
Mag. Nat. Hist. ser. 5, vol. xx. p. 256), and give a figure from a 
Capri specimen, and may repeat that the British Museum speci- 
mens of I. notomala, B., and I. Milneana, d’Orb., are so similar 
that they might be fragments of the same colony. The ovicell 
is figured from a rather broken-down specimen, and therefore 
there is some restoration of the zooecial tubes. 
