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Mr Gardiner , Notes on Variation , 
form in the British Museum 42 mm. in length. If the corallites 
continue to live, surely this should be exceeded in size from its 
locality. At the same time it is likely that in other places with 
less or more favourable environmental conditions the maximum 
may be above or below this. Thus in the Maldives Mr Forster 
Cooper and I dredged 8 dead forms, which averaged about 38 mm. 
(judging from two of the less decayed specimens brought home), 
the largest living form being 40 mm. 
In the smaller specimens the replacement of the escaped ova 
by fresh ova is quite clear. Occasionally before an egg escapes, 
the young ova are to be seen lying between the ovary and the 
mesenterial filament ready to take its place 1 . Indeed at no time 
is there a dearth or vacuity in the ovaries, whereas in the oldest 
forms the ova are separated from one another, and there are no 
signs of fresh ova being produced nor of the gaps being otherwise 
filled up. 
A somewhat similar phenomenon to the above is shown by 
a colonial coral, which I originally described from South Pacific 
specimens under the name of Goenopsammia willeyi 2 . This 
coral is common in the Maldives, seated on the under sides of 
stones of the boulder zone. All the separate polyps of a colony 
are of the same sex, male or female ; of protandry I have seen 
no suggestion. Further, all the separate colonies obtained by 
Dr Willey at Sandal Bay, Lifu, were of the same sex. Two 
colonies found at Minikoi in July, 1899, were both female, as 
were also seven collected at Hulule, Male Atoll, in January, 1900, 
on the same day, hence probably from a restricted area. Other 
colonies I have not examined, as two or more areas are or may be 
mixed together in my collecting jars. 
In addition the genital organs of the polyps of Goenopsammia 
willeyi in each of the above three collections are in the same state 
as those of other polyps of the same species from their own area. 
Thus in the Sandal Bay specimens the polyps were all females 
with ova separated from one another, but yet fairly regularly 
arranged. The ova are less regular in the Minikoi colonies, some 
having dropped out and not been replaced. In the Hulule polyps 
some of the ova touch one another, and are flattened on their 
1 Although I have examined a large number of specimens of Madreporaria of 
all kinds, I have not been able to satisfy myself as to the origin of the generative 
cells. The appearance in Flabellum suggests that they arise at the bases of the 
mesenterial filaments, and thence wander to their ultimate position. This, how- 
ever, is not confirmed in other species, and the question requires further examina- 
tion. It is interesting to observe that, should the generative cells be derived from 
the epithelium of the filaments, they would be ectodermic in their primary origin. 
For a consideration of the body layers in the Actinozoa vide “ On the Anatomy of a 
supposed new species of Coenopsammia from Lifu,” Willey's Zoological Results, 
Pt. iv., p. 374—5 (1899). 
2 Willey's Zoological Results, Pt. iv., pp. 357-380 (1899). 
