OVICELLS OF SOXIE LICHENOPOB^E. 
283 
Through Miss Jelly’s kindness I have been able to examine a 
considerable number of specimens of Lichenoporce from Victoria, 
and an abundant one is, I think, the L. echinata of MacGrillivray. 
The zooeeia are irregularly arranged, the peristome is much pro- 
duced on the proximal edge, namely, the margin nearest to the 
centre of the zoarium, sometimes with one process, sometimes 
divided into several ; numerous fine spines usually grow from the 
zooecial tubes as well as from the cancelli and the surface of the 
ovicell. The cancelli are angular with rounded corners, though 
when the tube is examined at some depth below the surface it is 
often seen to be round, and some of the cancelli may be called 
round, though that is not the usual character ; the entire inner 
surface of the cancelli is denticulate. The ovicell is formed by 
an inflated crust covering all the central area of the zoarium, and, 
as shown in figure 6, it starts from numerous places, ultimately 
meeting in the centre : at first this crust is very thin, but in the 
mature condition is deeply pitted ; the surface is then somewhat 
ribbed and there are numerous small pores at the base of the pits. 
In my previous paper to this Society (p. 277) I alluded to some- 
what similar pits in Hornera. 
As soon as the growth of the ovicell commences the basal reticu- 
lated cells of the central area are covered over by a thin pellicle 
with several perforations to each cancellus. Both the upper and 
under surface of the ovicell is shown in figure 6. Figure 3 is drawn 
from a specimen bent up at the two sides, and it is impossible to 
figure it satisfactorily, as it cannot all be seen in one focus. 
The opening of the ovicell is a wide tube low down at the 
border of the inflation, directed horizontally, much in the same 
way as in L. ciliatci (Ann. Mag. Nat. Hist. ser. 5, vol. xx. p. 263, 
pi. vii. fig. 5) ; but I have only seen the one ovicell of L. ciliatu 
spreading among the zooecial tubes, and these two forms seem so, 
closely allied that I am in doubt as to the basis of their distinction. 
In some specimens the zooeeia are slightly ridged, as in L. grig- 
nonensis. The spines from the zooecial tubes are not constant, 
sometimes occurring in great abundance, in others there are very 
few or they may be entirely absent. Both in this and L. prist is, 
MacGr., there is a semitransparent closure with a dull opaque 
disk in the centre, perforated in the middle. It seems probable 
that L. pristis and L. echinata are only the simple and confluent 
colonies of the same thing. 
Loc. Victoria; Tristan da Cunha (‘Challenger’). 
